Launch It

Materials (per rocket)

• balloon
• small lump of clay
• paper
• 1 wide straw
• 1 thin straw that fits inside the wide straw
• tape
• target (box lid or paper with a bull's-eye drawn on)
• scissors

We Challenge You To...

...design and build an air-powered rocket that can hit a distant target.

Brainstorm and Design

Think about things that might affect how your air-powered rocket flies.

• How long will your rocket be?
• How many paper fins will your straw rocket have—0, 2, or more?
• How will adding weight to the straw's nose or having fins affect how it flies?
• When you launch your straw rocket, how does the launch angle affect where it lands?

Build

1. First, build a balloon-powered launcher. Slide 1—2 inches (3—5 cm) of the thin straw into a balloon. Make a tight seal by taping the balloon to the straw.
2. Next, build a straw rocket. Use the wide straw for the rocket. Seal one end. Either plug it with clay or fold the tip over and tape it down.
3. Now launch your rocket. Blow into the thin straw to blow up the balloon. Slide the wide straw onto the thin straw. Aim. Launch!

Test, Evaluate, and Redesign

Set up a target. Stand 5 feet (1.5 m) away and try to hit it with your rocket. Can you make your rocket hit the target every time? Try these things if your rocket:

• falls quickly to the ground—Reduce the weight.
• misses the target—Launch it at a different angle.
• won't fly straight—See if fins make a difference. Also, try adding weight to the rocket's nose.
• sticks to the launch straw—Make sure the launch straw is dry. If it isn't, wipe it dry. Also, try blowing up the balloon more.