rocket science project hypothesis

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Classroom Activity

Simple rocket science.

Video of a rocket launch

Plastic milkshake straw

10 long party balloons

Clear cellophane tape

6-8 meters of nylon monofilament fishing line (any size)

Spring clothespin or binder clip

Rocket figure , colored and cut out

3 pieces of chart paper

Journal or sheet of paper (1 per student)

(Optional) Balloon hand pump

(Optional) Camera

• Set up the experiment in an area where students can all gather around and see clearly but stand back far enough to not interfere with the balloon travel.
• Prior to class, cut out (and color, if desired) the rocket figure.

NASA uses rockets to launch satellites and probes into space. NASA rockets are powered by burning solid, liquid or gas rocket fuel.

Long before the development of modern rockets, Sir Isaac Newton described the principles of rocket science in three laws of motion.

A simplified explanation of his third law of motion helps young students understand how rockets work. This law states that every action has an equal and opposite reaction.

When a rocket expels fuel or propellant out of its engine, the rocket moves in the opposite direction. The rocket pushes the propellant out, and the propellant then pushes the rocket. The propellant comes out of the engine. This is the action. The rocket lifts off the launch pad in the opposite direction. This is the reaction. In this activity, the rocket is a balloon propelled by air.

Launch of the GRACE-FO spacecraft on May 22, 2018. | Watch on YouTube

• Show students a video of a rocket launch. Note the direction that the rocket moves. Note where the engines are and where the flames or fire comes out.
• Ask students if they know how a rocket works. Explain to them that they will be conducting a simple demonstration or science experiment to show how a rocket lifts off the launch pad. Students, just like the astronauts in space and scientists on Earth, will conduct an experiment to gather information.

Image credit: NASA/JPL-Caltech | + Expand image

• Thread the fishing line through the straw, then attach each end of the line to the back of two classroom chairs. Pull the chairs apart to stretch the line tightly.
• Inflate a balloon and keep it tightly closed using fingers, a clothespin or a binder clip while carefully taping the balloon to the straw.
• Slide the balloon-straw assembly to the middle of the fishing line span.
• Show students the position of the balloon on the fishing line. Explain to the class that, in this experiment, an adult will release air from the balloon and students will predict what will happen.
• Introduce the word “hypothesis,” if appropriate. Show the class the word written on a piece of chart paper. For scientists, a hypothesis is a reasonable or good guess about what they think will happen in an experiment.
• Discuss the direction the air will move when it is released from the balloon. The balloon will also begin to move. Based on their prior experiences, ask the students to make a good guess about the direction the balloon will travel when air is released. Ask the class to verbalize their hypotheses, or guesses, about the movement of the balloon. Have students point with their fingers to indicate the direction in which they think the rocket will travel.
• Write the hypothesis developed by the class on the chart paper.
• When discussing the direction of movement, encourage the class to use the word “opposite.” Introduce or review the concept of opposites.
• To help students remember the correct sequence of events in the experiment, write directions or draw pictures to represent the steps on chart paper. Display the directions in the classroom.
• Ask students which way, based on their hypotheses, we should tape the rocket figure to the balloon. If necessary, remind students that the nose cone of the rocket points in the direction the rocket will travel. Use cellophane tape to attach the rocket figure to the balloon.
• Prepare to launch, or release, the air from the balloon. Just like a rocket launch, practice a countdown, “10,9,8,7,6,5 ... ,” before the air is released.
• Carefully remove fingers, clothespin or binder clip from the balloon and release the air. The balloon will travel in the opposite direction from which the air escaped.
• Ask students if their guesses or hypotheses were correct.
• Explain to students that scientists must repeat an experiment many times. Repetition of an experiment ensures that the results are accurate. Like scientists, the class must repeat the experiment with the balloon to determine that the results are always the same.
• Let students choose a reasonable number of times to repeat the experiment. Scientists need to have many repetitions to increase the reliability of their results.
• Before repeating the experiment, tell the class that scientists need a method to record the results from experiments.
• Ask the class to devise a simple way to record information or data from the experiment. For example, if the experiment repeats five times, ask students to write the numerals 1 to 5 on an individual sheet of paper or in a journal.
• Have students observe the experiment being performed a number of. Have students draw an arrow next to the numeral to indicate the direction the balloon traveled each time. Be sure students are only on one side of the rocket so arrow directions are consistent. Data collection could also be a class activity.
• Be ready to repeat the experiment the number of times suggested by the class. If necessary, use a new balloon blown up by an adult. When attaching the balloon to the straw, be certain that the open end of the balloon is always facing the same direction. Remember to practice a countdown. Collect data from the experiment.
• As the experiment repeats, let students participate by holding the balloon closed and releasing the air. Remind the class to observe the balloon’s movement and to record the data.
• Allow students to compare their data. Ask students if they can learn something or draw a conclusion from this information.
• If appropriate, introduce the word “conclusion.” Write the word "conclusion" on chart paper. A conclusion is a statement of the results from the experiment. Ask the class what they learned from the experiment. Write their conclusion on the paper. For example, the conclusion could be, “When the air was released from the balloon, the balloon moved in the opposite direction.”
• Discuss whether the original hypothesis or guess was correct. Have students verbalize why they think the balloon traveled in the opposite direction.
• Explain to students why the movement of the balloon is like a real rocket’s movement. If appropriate, introduce Newton’s third law of motion. In a rocket, propellant escapes from the bottom of the rocket. In the balloon experiment, air escapes from the end of the balloon. The balloon moves due to the escaping air providing a “push” to the balloon the same way a rocket lifts off due to the escaping propellant providing a “push” to the rocket. Also like a rocket, the balloon travels in the opposite direction of the escaping air.
• Display the chart paper with the hypothesis, the chart paper with the conclusion, and the data collection sheets in the room. If a camera is available, add pictures of the students conducting the experiment to the display.
• Observe students as they answer questions about the experiment.
• Have students draw a picture of the experiment in their journals or on a piece of paper. Ask them to explain their drawing and explain the relationship between the balloon’s movement and the released air.
• Ask students to describe how a rocket works.
• Challenge students to apply what they learned in this experiment. Repeat the experiment with one change. When attaching a balloon to the straw, reverse the placement of the open end of the balloon. If the open end was to the left, place it to the right. Ask students to form a hypothesis about the movement of the balloon when the air releases. Conduct the experiment. Repeat if necessary. Discuss whether the hypothesis was correct. Talk about the similarities and differences in this experiment and the original experiment. Ask the students if the balloon, in both experiments, moved in the opposite direction from the release of the air. Discuss how students applied what they learned or their conclusion from the first experiment to a new situation.
• Repeat the experiment with another variation. Change the position of the fishing line. Attach one end to the ceiling. Place the straw on the line and stretch the line tightly. Attach the balloon. Attach the other end of the line to a chair or object in the room. Repeat the experiment. Ask students to apply what they learned to a new situation.
• In a journal or on a sheet of paper, or as a group exercise with the teacher writing on chart paper, ask students to list the steps needed to conduct the experiment. Discuss the importance of completing the steps in the right order. Encourage the use of ordinal numbers, such as first, second and third in students’ descriptions.
• Have students use directional words to describe the movement in the balloon experiment or a rocket launch. Discuss words such as up and down, left and right, and forward and backward. Introduce or review the concept of words that are opposites. Have students generate a list of words that are opposites.
• Locate books that feature pictures and drawings of rocket launches. Encourage students to look at the depictions of rocket launches and think about what they now know about how a rocket works. Ask students to look at the pictures and note the direction in which the rockets move.

Do a Science Fair Project!

How do you do a science fair project.

Ask a parent, teacher, or other adult to help you research the topic and find out how to do a science fair project about it.

Test, answer, or show?

Your science fair project may do one of three things:

Test an idea (or hypothesis.)

Answer a question.

Show how nature works.

Topic ideas:

Space topics:.

How do the constellations change in the night sky over different periods of time?

How does the number of stars visible in the sky change from place to place because of light pollution?

Learn about and demonstrate the ancient method of parallax to measure the distance to an object, such as stars and planets.

Study different types of stars and explain different ways they end their life cycles.

Earth topics:

How do the phases of the Moon correspond to the changing tides?

Demonstrate what causes the phases of the Moon?

How does the tilt of Earth’s axis create seasons throughout the year?

How do weather conditions (temperature, humidity) affect how fast a puddle evaporates?

How salty is the ocean?

Solar system topics:

How does the size of a meteorite relate to the size of the crater it makes when it hits Earth?

How does the phase of the Moon affect the number of stars visible in the sky?

Show how a planet’s distance from the Sun affects its temperature.

Sun topics:

Observe and record changes in the number and placement of sun spots over several days. DO NOT look directly at the Sun!

Make a sundial and explain how it works.

Show why the Moon and the Sun appear to be the same size in the sky.

How effective are automobile sunshades?

Study and explain the life space of the sun relative to other stars.

Pick a topic.

Try to find out what people already know about it.

State a hypothesis related to the topic. That is, make a cause-and-effect-statement that you can test using the scientific method .

Explain something.

Make a plan to observe something.

Design and carry out your research, keeping careful records of everything you do or see.

Create an exhibit or display to show and explain to others what you hoped to test (if you had a hypothesis) or what question you wanted to answer, what you did, what your data showed, and your conclusions.

Write a short report that also states the same things as the exhibit or display, and also gives the sources of your initial background research.

Practice describing your project and results, so you will be ready for visitors to your exhibit at the science fair.

Follow these steps to a successful science fair entry!

If you liked this, you may like:

Learn STEM by Doing (and having fun)!

Science Fair Project: Alka-Seltzer Rocket Showdown

It was a warm, sunny afternoon, when they crept inside…  Mom!  We’re boooored!  I wanted to avoid the iPods or Netflix, so I scraped together supplies to make homemade baking soda/vinegar rockets to shoot off in the backyard.  Holy cow!  Lots of rocket FAILS that day!   I may still stink like vinegar…   After working through different materials, we came up with our favorite combination and the kids learned more about acid/base reactions.  In this post, we walk through how our kids learned how to build an Alka-Seltzer rocket.  What’s also great about this project is that it can be easily turned into a science fair project… let’s SCIENCE!!

SHORT VERSION OF THE EXPERIMENT (tl;dr) :  your kiddos will learn how to make a rocket using an empty 35mm film canister  “powered” by Alka-Seltzer and water.  Not a rocket scientist?  NO PROBLEM!  You can pull this off with most of the items already in your house, a trip to the dollar store, or of course, Amazon.  The experiment is probably best suited for 3rd graders and up, and beyond the basics of experimental design, they will learn about chemistry (acid/base reactions), physics (propulsion, motion), and the scientific method.  Basic data analysis (counting, comparing) can be used and if you snap some pictures along the way, during the construction and “launch”, setting up a science fair project board can be done in super easy fashion (like a single day)!

Edit: We recently learned a team at the University of Minnesota broke a Guinness World Record by blasting an Alka-Seltzer powered rocket 430 feet high!!! Whoa!!

Science fair project overview:  what we’ll do

Build an alka-seltzer rocket.

Hey STEMium readers!  In this project, you’ll be comparing different “rocket fuel” combinations for our homemade rockets to see which one flies the highest.  You will construct your rocket out of an empty 35mm film canister, paper/cardboard and other accessories as needed (who DOESN’T want a glitter fin??).  Then, you’ll use different ratios of our “rocket fuel” mix:  Alka-Seltzer in water.  Some rockets will get a lot of Alka-Seltzer.  Others will only get a little Alka-Seltzer, so we can see if more means a bigger liftoff.  Get ready to get messy as this one may leave some spills.  If you’re going to do it indoors ( not recommended ), you’ll need a tarp, really high ceilings (like in a gym) and possibly a mop/cleanup crew.

Who can do this project?  Age range: 3rd Grade and up

We first did this experiment with a 2 nd grader, a kindergartner, and a preschooler.  Later, we turned it into one experiment center at a science night out for 3rd-6th graders.  Looking at all the grade settings, I think the concepts were a bit more challenging to convey to the younger groups (although they definitely enjoy the launches!).  It would probably be better suited for older kids – 3 rd grade and beyond.  Younger kids can still participate and help design/build the rockets.

The Science Behind The Alka-Seltzer Rocket

Before we delve into the details of the experiment, let’s talk more about how we’ll get our rocket to blast off.  There is so much science goodness packed into these experiments it’s hard not to get too excited!!

The chemistry of alka-seltzer

We will be taking advantage of ACID/BASE reactions.  Specifically, our rocket fuel of choice will be a combination of Alka-Seltzer and water.  While we’ve experimented extensively with baking soda and vinegar, the bottles and general setup is a little more hit or miss (and waaaaay messier).  I’ll put some links in the appendix if you’d like to try to compare “rocket fuels”, but for now we will stick with building an Alka-Seltzer rocket.

A chemical reaction is occurring whether you use baking soda/vinegar or Alka-Seltzer/water — an acid and base reaction, to be exact.  There’s some great background info from Khan Academy on acids/bases for more info, but the simplest explanation is that ACIDS are materials that have a lot of hydrogen ions (H+)…  When an acid is combined with a BASE (a substance with a lot of hydroxide ions, OH-), we call this an acid/base reaction and the end result is usually the generation of a salt and water (and especially important in our case — carbon dioxide gas!).

Mixing acids and bases – how does alka-seltzer work?

As you can see from this picture, when you open the Alka-Seltzer package, it looks like a simple tablet.  Digging deeper, Alka-Seltzer is a combo product, meaning it contains both an ACID (anhydrous citric acid) and a BASE (sodium bicarbonate).  The “anhydrous” part means that it has no water…hence, why it’s individually packaged to keep moisture out.  When you drop the tablet into a glass of water, the acid/base reaction can begin as the two reagents (citric acid and sodium bicarbonate) come together.  The picture below shows what’s going on in the chemical reaction… by combining this acid and base, we create water, a salt (sodium citrate) and carbon dioxide (CO 2 ).

How Does The Rocket Take Off?

Back in 1686, Sir Isaac Newton formalized the key laws of motion… Newton’s third law is directly evaluated in our Alka-Seltzer rocket experiment:

<<For every action, there is an equal and opposite reaction>>

Check out this video below from Khan Academy for a good breakdown on Newton’s laws:

At this point you might be asking:  What does this mean and what does it have to do with bottle rockets??   Well, when the CO 2  pushes out of the rocket, the rocket pushes away from the gas.  Gravity is another force pulling the rocket, keeping it on the Earth, but when the force of the gas pushing the rocket becomes greater than gravity, the rocket lifts off.

Also keep in mind: SAFETY FIRST !  These are not space shuttle-like explosions, but there will be liquid spilling out quickly and broadly.  Assuming things are assembled properly, your rocket will blast off.  Wear eye protection if appropriate and do NOT aim the rocket at anyone or anything.

Materials – what you’ll need:

• Alka-Seltzer tablets – pop, pop, fizz, fizz . You are looking for the original effervescent tablets that fizz when dropped in water.  Not the chews.  Not the flavored kind.  You can try this link here .  We did not try Alka Seltzer Gold in our rockets, which contains two antacids (sodium citrate, potassium citrate) instead of just the one; however, I think it would most likely work the same.  Store brand product would also likely work out well.  Ideally, you want fresh material versus something that’s been sitting in a medicine cabinet for the last few decades.
• Water .   Just plain old water.  If you’ve got a tap (or bubbler as the fine folks of Milwaukee call it) then you are all set.
• Film canisters with lids – if you have some laying around the house, feel free to use any container that has a lid which will snap shut. If you’re like us though and haven’t used any film in the past decade, then cruise on over to Amazon.  We found this 12-pack of containers which should do the trick.  The seal that the lid makes with the container is important for the pressure to build up in the canister…so if you see people mentioning a flimsy lid, or poor seal in the reviews on Amazon, AVOID it and make a different selection.
• Construction paper/thin cardboard/index cards, scissors, markers/crayons, tape. The art supplies will be used to create the cone and fins on the rocket.  Get creative… if there are other lightweight materials that the kids are interested in adding (e.g. maybe glitter? Tinfoil?) go for it.
• Paper towel . Not necessary for the experiment but should make clean up a lot easier.
• Plastic drinking straws (optional) . We added these to our Alka-Seltzer rocket to work as a tripod landing gear — basically, the rocket stood on these three legs like a stool.  It just kept the bottom of the rocket (“top of the film canister”) off the ground at launch.  You can also use cardboard triangle cutouts to make fins.

Designing the Experiment:  Picking a Hypothesis

Like our other experiments, it all starts with selecting a hypothesis….  Remember, we will vary the amount of Alka Seltzer used in our rockets and compare which one blasts off the most.   What do we think will happen ?

Experimental Controls

This is a bit more challenging than our “ Germiest Spot in School ” experiment.  In that one, we had negative controls (bacterial plates with NO growth) and positive controls (bacterial plates with COMPLETE growth).  For our rocket experiment, one negative control might be a rocket with only water (but it’s kind of a bummer because it’s something that won’t fly).  Positive controls are a little trickier to come by though.

CHECKPOINT :  At this point, you should have a hypothesis about which rocket will fly higher, and why.  You may also have a few other variables you are testing… here’s what we wrote down:

• Hypothesis : the Alka-Seltzer rocket with a full tablet will fly further than the baking soda rocket
• Variable – Alka Seltzer : we made one rocket with a ¼ of a tablet, one rocket with a ½ of a tablet, one rocket with one full tablet, and one rocket with a tablet all ground up.
• Controls : you can do a negative one if you’d like.

Here’s our grid:

Methods/Procedure – How we’re going to complete our rocket build:

The steps listed below are how we completed our rocket project as an experiment; but please note, we did not enter this one as a science fair project.  You should be able to do this one as either approach — if you will be turning it into a science fair project, make sure you taking good notes and pictures to document everything.   In terms of how long it will take you, there’s about 15-30 minutes of setup/prep time (this is mostly designing the rocket — the creative part of the project), about 30 minutes for setting up reactions and launching rockets, and about 30 minutes to compare launches and analyze the data.  Assuming you have all the materials you need, you could get this one done in a single afternoon.

Time to build:  Alka-Seltzer rocket…

• Creative time! Decorate the rocket .  The opening of the film canister will serve as the bottom, so it will be firing with the lid end on the ground and the bottom end on top.  Cut enough construction paper to wrap around the film canister and decorate however you’d like.  Use the tape to stick onto the container.  Also create a rocket nose cone out of paper and tape to the “top” of the rocket (“bottom of the film container”).  If you’d like to create fins, you can also add those on.  You can also now fix on your rocket “legs” with the straws by taping three to the sides.  Make sure the rocket can stand upright and doesn’t tip over.
• Launch prep . Turn the rocket upside down to load the water in the container… fill it ~1/4 to ½ of the way full.  Make sure to note HOW MUCH water you added, so you have your combinations ready to test (look back at your chart if you need to keep track).
• LAUNCH ***need to move quickly here!*** . Break an Alka Seltzer tablet in half (or fourths or leave whole, depending on which tube you are loading) and add the tablet in the container with the water.  QUICKLY!  CLOSE THE CONTAINER – make sure to snap the lid on completely.  Set the rocket on the ground upright (lid side down at the ground).  Stand back and count down the launch.
• BOOM! Use a landmark or object to gauge how high the rocket made it.  Mark it down in a notebook or sheet of paper.  Also note how much “rocket fuel” was used – was it half a tablet and half full with water?

Data Analysis – What does the data tell us?

Congratulations!  You’ve officially built and launched rockets!

Hopefully, you’re not completely covered in a mess at this point and you have had some successful launches!  Which rocket flew the farthest?  Were any duds?  Was your original hypothesis correct?  How about testing the different variables – did adding more Alka-Seltzer to the rocket create a more powerful rocket?  If you did multiple rockets of the same kind (“replicates”), did they all fly the same or did some work better than others?

Your data analysis table might look something like this:

Conclusions – what we learned from the Alka-Seltzer rocket experiment; did it work?

Hopefully, the kiddos have a good idea about which rocket worked better or best. Hopefully, they also have a general understanding of what happens when you combine an acid and a base.  Most importantly, hopefully they had fun!!

Other things we’ve tried

After some fine tuning, we originally incorporated Alka-Seltzer rockets at a STEM outing and based it off of the Alka Seltzer science experiments site .  Overall, our rockets blasted off pretty easily with the majority successfully reaching some pretty good heights.

Now, separately, we have also tried the baking soda/vinegar rockets at home one summer day, but after getting drenched in about a gallon of vinegar we eventually abandoned our efforts that were based on this posting that we found using empty water bottles and a soda bottle .  While we had plenty of bottles, and we were even able to make the baking soda packets pretty easily, we struggled with corks that could fit tightly enough in the bottles.  The result:  tons of messy spills and leaks.  No takeoffs and bored kiddos.

While the baking soda/vinegar rockets will likely give you a bigger “boom”, they’re definitely more challenging to set up… from the starter perspective, if this is your first time, I’d opt for the Alka Seltzer/water setup in the film canisters to save your sanity.  Hands down – the Alka-Seltzer rocket strategy was far easier to maneuver and to keep the kids engaged.

Our results

As you can see from some of the pictures here, our Alka-Seltzer rocket with the most tablets flew the farthest.  As we increased the amount of Alka Seltzer in the container, we definitely noticed a stronger reaction taking place.  Interestingly, we couldn’t get much of a pop with the ground up tablet rocket.

Next steps – what are some follow up experiments?

There are a TON of different variables you can experiment with in the Alka-Seltzer rocket projects, which makes it fantastic to use for a science fair project.  Here are a few concepts/variables to further explore:

• Different solutions (besides water). What if you dissolved the Alka-Seltzer tablets in something besides water?  How would the reaction proceed if it were an acidic solution like orange juice? Vinegar?
• Different temperatures. What if you added ice, cold water to the container?  Would it change the intensity of the blastoff?  What about hot water?
• NASA – parts of a rocket
• https://media.nationalgeographic.org/assets/file/Seltzer_Rocket_Lab_Activity.pdf
• Check out the original Alka-Seltzer site to get great ideas and pics for not only the Alka-Seltzer rocket, but other Alka-Seltzer-based experiments:  https://www.alkaseltzer.com/science-experiments/

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Science Fair Guide: Straw Rocket

In addition to the straw rocket materials , you’ll need a tape measure and craft foam.

Ask a Question

What amount of added mass causes the rocket to fly the farthest?

Gather Information

Air is made up of countless molecules: oxygen, carbon dioxide, etc. When these molecules bump into moving things, it slows those things down. This is a force called drag .

Flying things – like the straw rockets – need some mass to overcome drag. Mass is just how much matter (like molecules) is grouped together in an object. For example, a marble has more mass than a piece of popcorn. An object with more mass can more easily push past the air and resist drag.

If there's too little mass, then the drag will slow down the rocket before it’s travelled very far. However, too much mass, and the rubber band won’t be able to supply enough energy to get the rocket moving.

One last piece of information: a standard 4" mini glue stick weighs almost exactly 4 grams.

Make a Hypothesis

Using the information above, make an educated guess about how much mass will work the best. Your hypothesis should be a simple statement, such as: “5 grams of mass will cause the rocket to fly the farthest” (This is not necessarily the best hypothesis; it’s just an example).

Conduct an Experiment

Create one straw rocket, but don’t add any mass, like a piece of a hot glue stick, to the tip yet. Build the fins out of craft foam. You’ll be reusing this rocket quite a few times, and foam is much more durable than paper. You may want to make a second, identical backup rocket in case the first one gets too damaged.

Without any extra mass added, launch the rocket straight forward three times and record the distance travelled with a tape measure.

​Add a very small amount of mass (hot glue stick) to the tip. About a ½"-long piece is a good place to start. Launch three times again.

Remove that glue stick, and add a piece that’s ½" longer, then launch three times again.

Repeat until an entire 4"-long glue stick has been added to the rocket.

Setup the Controls

Controls are measures put in place to prevent unintended things from affecting your results.

Follow these procedures to ensure your data is accurate:

Stretch out the slingshot’s rubber band with your hands before beginning. The rubber band loosens quite a bit when it’s first used. Pre-stretching it will help ensure that each shot uses the same amount of energy as the one before it.

Make sure to fire straight ahead each test. Avoid aiming even slightly up or down.

Make sure to pull back the same amount for each test. Optional: Attach a ruler perpendicularly to the slingshot so you can pull back a precise amount each test.

After each test, inspect the rocket for damage. Make only the smallest repairs necessary. Avoid replacing fins or adding extra tape! These things can have a big effect on how far the rocket flies.

If you mess up a test (e.g. the rocket hits the slingshot when launched), then discard that result and test again. Record any discarded tests, and write a note about why you decided to retest.

Launch the rockets when it’s not windy.

Collect Data

Record the distance of each test. When finished, add up the results for each amount of mass added, then divide by 3 to get an average distance. For example, if a rocket with the mass of ½" of a glue stick flew 121", 102", and 93", then 121+102+93 divided by 3 is an average of 105.3".

Your data might look something like this (this is not real data; don’t use in your conclusion):

View the Rocket project

Make Observations

Describe any additional observations you made during the experiment. Be sure to include things might have affected your results such as launching errors, wind during some tests, or anything else unexpected.

Draw Conclusions

Look at your data and conclude which amount of weight caused the rocket to fly the farthest.

Present Findings

Present your main conclusion in a visual form, such as writing the average distance flown next to each piece of glue stick, and creating a graph that shows the distance the each one travelled.

Summarize your hypothesis, experiment method, the controls you put in place, and your raw data.

Write your conclusion, and explain why you think the results are the way they are.

Science Fair Central

Scientific Steps

Students who want to find out things as a scientist, will want to conduct a hands-on investigation. While scientists study a whole area of science, each investigation is focused on learning just one thing at a time. This is essential if the results are to be trusted by the entire science community.

Follow the Scientific Steps below to complete your scientific process for your chosen investigation, How do fins on a rocket affect its flight?

What is tested? Size of fins

What stays the same? Shape and number of fins, fin placement, type and size of rocket, propulsion system (amount of push), air movement, temperature, launch site

Data collected: Distance the rocket flies or trajectory (how straight the rocket flies)

What do scientists think they already know about the topic? What are the processes involved and how do they work? Background research can be gathered first hand from primary sources such as interviews with a teacher, scientist at a local university, or other person with specialized knowledge. Or use secondary sources such as books, magazines, journals, newspapers, online documents, or literature from non-profit organizations. Don’t forget to make a record of any resource used so that credit can be given in a bibliography.

After gathering background research, the next step is to formulate a hypothesis. More than a random guess, a hypothesis is a testable statement based on background knowledge, research, or scientific reason. A hypothesis states the anticipated cause and effect that may be observed during the investigation.

Consider the following hypothesis: If ice is placed in a Styrofoam container, it will take longer to melt than if placed in a plastic or glass container. I think this is true because my research shows that a lot of people purchase Styrofoam coolers to keep drinks cool.

The time it takes for ice to melt (dependent variable) depends on the type of container used (independent variable.). A hypothesis shows the relationship among variables in the investigation and often (but not always) uses the words if and then.

Design Experiment

Once a hypothesis has been formulated, it is time to design a procedure to test it. A well-designed investigation contains procedures that take into account all of the factors that could impact the results of the investigation. These factors are called variables.

There are three types of variables to consider when designing the investigation procedure.

• The independent variable is the one variable the investigator chooses to change.
• Controlled variables are variables that are kept the same each time.
• The dependent variable is the variable that changes as a result of /or in response to the independent variable.

Step A – Clarify Variable

Clarify the variables involved in the investigation by developing a table such as the one below.

Step B – List Materials Make a list of materials that will be used in the investigation.

Step C – List Steps List the steps needed to carry out the investigation.

Step D – Estimate Time Estimate the time it will take to complete the investigation. Will the data be gathered in one sitting or over the course of several weeks?

Step E – Check Work Check the work. Ask someone else to read the procedure to make sure the steps are clear. Are there any steps missing? Double check the materials list to be sure all to the necessary materials are included.

Data Collection

After designing the experiment and gathering the materials, it is time to set up and to carry out the investigation.

When setting up the investigation, consider...

Carrying out the investigation involves data collection. There are two types of data that may be collected—quantitative data and qualitative data.

Quantitative Data

• Uses numbers to describe the amount of something.
• Involves tools such as rulers, timers, graduated cylinders, etc.
• Uses standard metric units (For instance, meters and centimeters for length, grams for mass, and degrees Celsius for volume.
• May involve the use of a scale such as in the example below.

Qualitative Data

• Uses words to describe the data.
• Describes physical properties such as how something looks, feels, smells, tastes, or sounds.

As data is collected it can be organized into lists and tables. Organizing data will be helpful for identifying relationships later when making an analysis. Using technology, such as spreadsheets, to organize the data can make it easily accessible to add to and edit.

Analyze Data

After data has been collected, the next step is to analyze it. The goal of data analysis is to determine if there is a relationship between the independent and dependent variables. In student terms, this is called “looking for patterns in the data.” Did the change I made have an effect that can be measured?

Recording data on a table or chart makes it much easier to observe relationships and trends. There are many observations that can be made when looking at a data table. Comparing mean average or median numbers of objects, observing trends of increasing or decreasing numbers, comparing modes or numbers of items that occur most frequently are just a few examples of quantitative analysis.

Besides analyzing data on tables or charts, graphs can be used to make a picture of the data. Graphing the data can often help make those relationships and trends easier to see. Graphs are called “pictures of data.” The important thing is that appropriate graphs are selected for the type of data. For example, bar graphs, pictographs, or circle graphs should be used to represent categorical data (sometimes called “side by side” data). Line plots are used to show numerical data. Line graphs should be used to show how data changes over time. Graphs can be drawn by hand using graph paper or generated on the computer from spreadsheets for students who are technically able.

These questions can help with analyzing data:

• What can be learned from looking at the data?
• How does the data relate to the student’s original hypothesis?
• Did what you changed (independent variable) cause changes in the results (dependent variable)?

Draw Conclusions

After analyzing the data, the next step is to draw conclusions. Do not change the hypothesis if it does not match the findings.The accuracy of a hypothesis is NOT what constitutes a successful science fair investigation. Rather, Science Fair judges will want to see that the conclusions stated match the data that was collected.

Application of the Results: Students may want to include an application as part of their conclusion. For example, after investigating the effectiveness of different stain removers, a student might conclude that vinegar is just as effective at removing stains as are some commercial stain removers. As a result, the student might recommend that people use vinegar as a stain remover since it may be the more eco-friendly product.

In short, conclusions are written to answer the original testable question proposed at the beginning of the investigation. They also explain how the student used science process to develop an accurate answer.

Kids Workshops

To learn more visit, homedepot.com/kids

Kids Workshops provide a mix of skill-building, creativity, and safety for future DIYers every month in Home Depot stores across the country. After registering for the next Workshop, download these exclusive extension activities from Discovery Education. Each extension provides opportunities to reimagine or use their Workshop creation in an unexpected new way.

Grill Gift Card Box

Blooming Picture Frame

Use nature as inspiration for creative writing.  Students will research a variety of flowers to create a poem for their Blooming Picture Frame.

Lattice Planter

Explore the features of plants and consider how they impact our world. Students will select the type of plant they want to grow and map out a watering schedule to ensure it thrives in their Lattice Planter

Science in School

Rocket science made easy teach article.

Author(s): Ole Ahlgren

Prepare for lift-off with these simple activities that demonstrate some of the key principles of space science.

The term ‘rocket science’ is often used to explain something that is difficult to understand. While designing and testing rockets is a complicated endeavour that requires skill and plenty of brainpower, it is possible – thanks to some simple activities – to explain some of this complex science to your students.

This article outlines a collection of activities suitable for students aged 8–14 years. They are designed to be carried out in a workshop, which can be completed in around 2 hours. If less time is available, however, some of the demonstrations can be omitted or can be spread out over successive lessons. The activities can be adapted for secondary school students, by including more theory and relevant formulas. Note that many of the activities are available to view in a video w1 .

Activity 1: Launching a rocket balloon

Rockets are a perfect example for learning about forces and Newton’s laws of motion. During lift-off, there are two forces acting on a rocket: thrust pushes it forwards by expelling gases in the opposite direction, and gravity pulls it downwards. Once a rocket is moving, drag acts on the rocket in the opposite direction to its motion. The rocket will continue to speed up as long as the force of thrust is greater than the combined forces of gravity and drag. 

In this experiment, a rocket launch is illustrated by blowing up a balloon and letting it go. The escaping air exerts a force on the balloon, and the balloon reacts by pushing in the opposite direction with the same force, as described by Newton’s third law of motion (for every action, there is an equal and opposite reaction). The opposing force (as with rocket thrust) propels the balloon forward (figure 1). To make the demonstration more controlled, the balloon is attached to a line made from string.

• Balloon (ideally a long balloon)
• String (approximately 5 m in length)
• Clamp stands
• Tie one end of the string to a clamp stand that is attached to a table.
• Cut the straw in half across the middle, and thread the two halves of the straw onto the free end of the string. If you use a regular balloon (rather than a long balloon) this is not necessary.
• Tie the end of the string onto another clamp stand, ensuring that the string is pulled tight.
• Inflate the balloon and hold the end closed – do not tie the balloon.
• Fasten the balloon to the straws using tape (figure 2). You may find it easier to do this in pairs.
• Pull the balloon to one end of the string. Release the balloon and watch it propel along the string. Who can launch their balloon the furthest?

Activity 2: Boiling water in a vacuum

The pressure inside the International Space Station (ISS) is similar to the pressure on Earth, which is 1 atm. Outside the ISS, however, the pressure is about 10 -12  atm. If an astronaut were to travel outside the ISS without a space suit, any moisture – such as the saliva on their tongue or the water in their eyes – would begin to boil. This is because the lower pressure reduces the boiling point of water. A liquid boils when its vapour pressure (which increases with temperature) is equal to the external air pressure. The very low external pressure – close to a vacuum – would also make air flow out from the lungs, and the astronaut would lose consciousness from lack of oxygen w2 .

One way to observe this effect for yourself is by placing a glass of room-temperature water inside a vacuum chamber. Pump out the air from the chamber, and observe the water boiling. The first bubbles that appear are likely to be from air dissolved in the water, but soon after it will be the water itself that boils.

If your school does not have access to a vacuum chamber, the experiment can be performed with a syringe, as outlined below.

• Clear plastic syringe
• Syringe valve (optional)
• Water (heated to different temperatures)
• Place the syringe into a beaker full of water heated to approximately 37°C (body temperature). Pull back the plunger to take in a few millilitres of liquid.
• Remove the syringe from the beaker. Hold a finger (or place a valve) over the opening of the syringe and pull back the plunger. The water will start boiling (figure 3).
• Push the syringe in the opposite direction, and the boiling will stop.
• Repeat the demonstration with water of different temperatures. What do you observe?

When you pull back the plunger of the syringe, you increase the volume inside the syringe, resulting in a decrease in pressure. The pressure is now lower inside than outside the syringe. If cooler water is used (e.g. at room temperature), its vapour pressure will be lower, so the external pressure needs to be reduced more for the water to be at boiling point.

Activity 3: Overcoming air resistance

Galileo famously concluded that all objects fall at the same speed, regardless of their mass. We now know that, while this is true if there is no air resistance, this isn’t usually the case on Earth. In the hammer-feather drop experiment performed on the Moon during the Apollo 15 mission, astronaut David Scott held out a hammer and feather and dropped them at the same time w3 . Both objects fell at exactly the same rate; since the Moon has no atmosphere, there was no air resistance. When dropping the same objects on Earth (in normal air), the feather falls much more slowly than the hammer, as the downward force of gravity is greater for the object with the greater mass. This means the opposing force of air resistance affects the feather more than the hammer (figure 4).

This principle can be easily demonstrated by using a vacuum chamber. A piece of paper and a steel ball can be used for the objects, as shown in our video w1 .

Even without a vacuum chamber, you can demonstrate a similar effect by using only a coin and a piece of paper in the manner described below. Here, in addition to the forces of gravity and air resistance acting on the objects, aspects of fluid dynamics come into play.

• Cut out a piece of paper, ensuring that it is smaller than the coin (figure 5).
• Place the paper on top of the coin and hold the coin between two fingers.
• Drop the coin from a height of about 1 metre. Notice how the paper ‘sticks’ to the top of the coin and that they land simultaneously.
• Now drop the paper and the coin separately but at the same time. Notice how the paper falls much more slowly than the coin.
• Cut out a piece of paper that is bigger than the coin.
• Place the paper on top of the coin, and drop the coin again. Notice how the paper does not ‘stick’ to the top of the coin this time.

When the coin falls, it pushes aside the air in front of it. If a smaller piece of paper is placed on top of the coin, the air in front of the paper is also pushed aside. As a result, the paper falls at the same rate as the coin. If the paper is bigger than the coin, the coin cannot push aside all the air in front of the paper, and the paper’s fall is slowed by air resistance.

Web References

• w1 – The author has produced a video showing the activities carried out in his workshop.
• w2 – To understand what happens to the human body in a vacuum, visit the NASA website and read their library of past questions and answers (see question 5) about being an astronaut.
• w3 – The famous drop experiment from the Apollo 15 mission is available to view on YouTube .

Ole Ahlgren teaches physics, chemistry, biology and astronomy at Roende Gymnasium, a secondary school in Denmark.

This article sheds light on a topic that is usually considered particularly challenging, especially by primary school teachers. Each experiment involves a different physics concept (such as reaction forces or air pressure), but they are all connected by the common theme of space. Teachers can carry out all the experiments at once if they want to approach the subject as a whole, or they can pick individual activities to teach alongside the appropriate teaching unit. Overall, the article is very useful for both upper primary and lower secondary levels.

Dr Christiana Nicolaou, Archangelos Elementary School, Cyprus

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Science Project Ideas

Tea Bag Rocket

Here is a visually effective procedure that will help kids grasp the basic convection current phenomenon in physics. Adult supervision is a must for the homemade rocket.

Tea Bag Rocket Science Experiment

On lighting an empty cylindrical tea bag from the top, it flies upwards resembling a rocket.

• Non-inflammable plate
• Lighter or match

Instructions

• Remove the staple, string, and label from the tea bag.
• Clear off the tea from inside.
• Unfold the bag and spread it out.
• With your fingers, prop its inside to make it stand as a cylinder on the plate.
• Use the lighter to ignite its top.
• Wait for a few seconds to watch your rocket take off.

If you want, instead of step 1 you can cut off the top of the tea bag with a pair of scissors.

Tea Bag Rocket Video

How does it work: explanation.

The fire on top heats the air inside the tea bag, making it less dense (lighter) than the surrounding air outside. Due to convection, lighter air tends to move upwards while cool, dense air comes down to take its place. As a result, the tea bag flies up. As the flame reaches the bottom of the bag, it turns into ash and decreases in its mass. This aids the uplifting process even more.

The same principle is utilized in hot air balloons. A flame is lit at the base of a hollow balloon that heats up the air inside making it less dense than atmospheric air and raising it up in the process.

Magic tea bag rockets can be used as either a lab demonstration or a science fair project. Owing to its simplicity, the trick can be done at home to make science interesting for kids.

Balloon Rocket Science Experiment – A Balloon that Flies like a Rocket

3-2-1 Blast Off! This simple and fun science experiment teaches children about Action and Reaction. Using everyday household items, children learn how the force of air moving in one direction can propel balloon in the opposite direction, much like a rocket!

Below you’ll find a supplies list of everything you need, printable instructions, and the scientific explanation of how it demonstrates Newton’s Third Law of Motion in a fun, hands-on way. It’s so much fun, your kids will want to do it over and over with balloons of different shapes and sizes. 

JUMP TO: Instructions | Video Tutorial | How it Works | Lab Kit

Supplies Needed

• Drink Straw
• Two objects of the same height that you can tie a string to. We used two chairs

Balloon Rocket Science Lab Kit – Only $5

Use our easy Balloon Rocket Science Lab Kit to grab your students’ attention without the stress of planning!

It’s everything you need to  make science easy for teachers and fun for students  — using inexpensive materials you probably already have in your storage closet!

Balloon Rocket Science Experiment Instructions

Wondering how to create a balloon rocket? It’s easy! Simply follow these step by step instructions.

Step 1 – Position two objects of the same height (We used chairs) about 10 feet apart. Then grab your string and securely tie one end to one of the objects. 

Step 2 – Next, get your plastic drinking straw. If you are using a “bendy” straws with the flexible piece on one end, cut off the flexible part so you are left with a straight straw.

Thread the string through the straw and place two pieces of tape near the middle of the straw. P osition the two pieces of tape near the middle of the straw is important because if you place them near the ends of the straw, the straw will bend when the balloon deflates and the rocket won’t move as quickly.

Step 3 – Then tie the loose end of the string to your second object (We used a second chair across the room) and make sure the string is tight. If the string isn’t tight, move the objects farther apart until it is.

Step 4 – Blow up the balloon and hold the end so the air can’t escape and use the two pieces of tape to secure the balloon to the straw.  

Take a moment to make observations. What do you think will happen when the you let go of the end of the balloon? Write down your hypothesis (prediction) and then continue the experiment to test it out and to find out if you were correct.

Then move the straw and balloon to one end of the string. And once you are ready….

Step 5 – Let go of the balloon and watch what happens! Do you know what caused the balloon to rocket across the room? Find out the answer in the how does this experiment work section below. Then inflate the balloon again and repeat again and again.

Balloon Rocket Science Experiment Video Tutorial

How Does the Science Experiment Work?

The balloon flies across the string because of air and thrust. Thrust can be explained by Newton’s Third Law of Motion . Newton’s third law states that for every action there is an equal but opposite reaction. As the air is released out of the balloon in one direction, the force propels the balloon in the other direction. This equal but opposite force causes the balloon to fly across the string like a rocket!

I hope you enjoyed the experiment. Here are some printable instructions:

Balloon Rocket Science Experiment

• Two objects of the same height that you can tie a string to. I used chairs.

Instructions

• Position two objects of the same height (I’m using chairs) about 10 feet apart and grab a piece of string.
• Tie one end of the string to one of the objects. Make sure it is securely fashioned.
• Next, get a straight plastic drinking straw. If the straw is one of the “bendy” straws with the flexible piece, cut off the flexible part so you are left with a straight straw.
• Place two pieces of tape on the straw. Note: Be sure to position the two pieces of tape near the middle of the straw. If you put them near the ends of the straw it will bend when you blow up the balloon and the rocket won’t move as quickly.
• Thread the string through the straw
• Tie the loose end of string to the back of your second object (I’m using another chair) and make sure the string is tight. If the string isn’t tight, move the objects farther apart until it is.
• Blow up the balloon and hold the end so the air can’t escape and use the two pieces of tape to secure the balloon to the straw.
• Move the straw and balloon to one end of the string. And once you are ready…..
• Let go of the balloon and watch as it rockets across the string! Then inflate the balloon again and repeat again and again.

Reader Interactions

March 30, 2016 at 11:05 pm

you balloon rocket is so cool!

– Misk Algaysi

May 10, 2017 at 6:20 pm

The balloon wind is pushing against the regular wind which makes it fly and the rope is inside the straw which also makes it go faster.

October 28, 2018 at 10:27 pm

Cool experiment. The balloon flew like a rocket!

June 8, 2023 at 7:55 am

This is a really cool experiment! I am going to try this for my science experiment.

— Matthew Jensen

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