Instructions

  • 1

    Here are some of the materials you can use

    • 1 balloon
    • box lid 
    • clay (small lumps for weights)
    • marker or tape (to make a bulls-eye)
    • paper
    • ruler 
    • scissors
    • tape
    • 1 thin straw (that fits inside the wide straw)
    • 1 wide straw
  • 2

    Prepare ahead of time

    • Have paper and pencil ready to write down ideas and sketches as you design.
    • Make a target by drawing a large bull’s-eye on a sheet of paper or on a box lid. 
    • Set up a target area and place your target in the center.
  • 3

    Think about the challenge

    • What is a rocket?
    • What are the different parts of a rocket?
    • What are some different ways to launch a rocket?
    • How does a rocket get thrust into space?
    • TIP: NASA uses rockets to get to the moon. A rocket is basically a huge engine that lifts things into space. Some rockets carry astronauts into space while others carry a space shuttle, a satellite, or another piece of space equipment. 
    • TIP: The large column of the rocket is called the body. The fins stick out at the lower end of the body. The small capsule at the top of the body is the nose cone—that’s where the astronauts sit. 
  • 4

    Think about and write down a few ideas

    • What size will your rocket be? 
    • Think of ways to send your rocket into the air. How will you power your rocket? 
    • How could you change the speed of your rocket, how high it flies, and the distance it goes? 
    • How will you make sure your rocket flies in a certain direction in order to hit the target? 
    • TIP: Inventors’ and engineers’ first ideas rarely solve a problem. They brainstorm ideas, try different ideas, learn from mistakes, and try again. This is part of the design process
  • 5

    Look at the materials

    • What materials do you have to build the different parts of the rocket?
    • What material will you use as fins? How many fins will you add to your rocket?
    • What will you use as a launcher for your rocket?
    • How will you power your rocket with the materials you have?
    • TIP: Blowing up a balloon stretches the rubber, which stores energy as potential energy. When the pressurized air inside the balloon rushes out, the potential energy changes to motion energy (kinetic energy), making the rocket move. 
  • 6

    Design and build a straw rocket

    • Decide what features might help your rocket hit the target. 
    • Think about features such as weight or fins.
    • Add the features to your rocket to help thrust or push it forward. 
    • TIP: If you can’t thrust your rocket into the air with the power source, try taking some weight off the rocket.
    • TIP: Engineers often redesign parts of their original ideas to make them better. Take notes on things such as the length of your rocket, the weight of the nose cone, or the number of fins you use in case you need to redesign some of the parts. 
  • 7

    Design and build a balloon-powered launcher

    • Slide the thin straw into the balloon.
    • Decide how you will seal the balloon so the air stays in the balloon. 
    • Blow into the straw to be sure the seal is tight.
    • TIP: If the balloon deflates, air is escaping and you need to tighten the seal. If the balloon stays inflated, you have a tight seal.
  • 8

    Test the launcher

    • Decide how much air you want in the balloon and Inflate the balloon.
    • Pinch the straw to keep the air in the balloon.
    • TIP: The amount of air in the balloon will affect the thrust of the rocket. The more air (pressure) in the balloon, the more power there will be to thrust the rocket forward.
    • TIP: You can test a design at different steps along the creation process. This way you can spot a problem when it happens instead of at the end of the process. 
  • 9

    Get in position

    • Decide on the launch location for your rocket.
    • Choose the angle for the launch. 
    • TIP: You can change the travel distance and shape of the flight path your rocket takes by changing the angle of the launch. 
    • TIP: Launching a rocket straight up sends it high but not far; straight out makes it fall quickly to the floor.
  • 10

    Launch it

    • Slide the rocket onto the launcher.
    • Aim your rocket at the target and send it flying!
    • TIP: If the rocket misses the target, try launching it from a different angle.
    • TIP: If the rocket won’t fly straight, try adding fins to the rear or middle of the rocket. 
    • TIP: If the rocket sticks to the launch straw, try wiping the launch straw off to make sure it’s dry. Or you might try blowing up the balloon more.
  • 11

    Did you know?

    • How Things Have Changed! 
      Today’s rockets travel fast, far, and for a long time. One rocket, called Voyager 1, has been traveling for more than 35 years and is now over 11 billion miles (18 billion km) from Earth! The rocket is powered by electricity that comes from converted heat. The rocket carries special pellets made from a chemical compound that release heat when they decay. This heat turns into electricity. The Voyager 1’s power isn’t expected to be completely gone until about 2025.

      That’s quite a change from the early days when the first liquid-fuel rocket, built in 1926 by Robert Goddard, flew for only 2½ seconds and went just 41 feet (12.5m). Talk about improving a design! 
  • 12

    Try this next!

    • See how far can it go. Test how far your rocket goes on each breath of air. Fill the balloon with three breaths of air. Launch it and then measure how far it travels from its launch point. Repeat with five, seven, and nine breaths—but keep the launch angle the same. Record the results by plotting the distance traveled against number of breaths. 
    • Different angles get different results. Experiment with different launch angles. Use a protractor to position a book cover or a sheet of cardboard at a series of various angles, such as 30, 45, 60, and 90 degrees. Launch the rocket at each angle, record the distance it travels, and compare how far it goes each time.