Bottle Rockets!

During the week of June 2nd, our science class has been building bottle rockets out of two-liter soda bottles, duct tape, card stock, and cardboard. We had about two hours. We (Killer Science) created a bottle rocket that traveled 76 meters (almost 250 feet). Here's how to make one yourself.

Materials: 
- one empty two-liter soda bottle
- one roll of duct tape (any color works)
- one sheet of card stock
- a plastic bag w/ 100 grams of sand inside
- 500 ml of water
- scissors

Procedure:
1.) Cut out three 3 in. by 4 in. by 5 in. right triangles out of cardboard
2.) Cut out three 6 in. by 7 in. by 8.5 in. right triangles out of cardboard
3.) Tape the smaller triangles about 3 in. from the top (the end that you don't normally drink out of) of your two-liter bottle . Space them equally around the bottle, then use the duct tape to secure them. Make sure that the wings are secure or else they will fall off during the launch.
4.) Tape the larger triangles 6 in. from the top (the end you don't normally drink out of) of your bottle, between the smaller triangles. Again, make sure to secure the wings.
5.) Use the card stock to create a circle with a 4 in. radius. Using a compass is best, but freehand works, too. Then, cut from the outer edge of the circle directly to the center. Fold it into a cone shape.
6.) Put the plastic bag w/ 100 grams of sand inside your cone and duct tape it to what will be the front of your rocket.
7.) Duct tape over any rough edges or folds of tape to reduce wind resistance during flight. This will slow down the rocket, and it will not travel as far.
8.) Pour the 500 ml of water into your rocket. You may want to use a funnel to help prevent spilling.

Note: It is incredibly important that during the process of building your rocket that you do not damage or puncture it. Your rocket will not be able to build up pressure and therefore will not fly if this happens.