Article: For this rocket, you will need one water bottle, one pen, one foam football, duct tape or hot glue, and cardboard. You can really use any type of water or soda bottle. For a larger rocket use a two-liter soda bottle. Remove label (if applicable) and discard. Take the cap off, but save it. You will need it later. At this point, you may want to consider decorations like paint, stickers, colored duct tape and the like.  (You can decorate later, but it may be easiest at this stage). Bic Pens work great. Remove all parts and set them aside. Use caution when handling these components of the pen. It is easy for the ink cartridge to explode. Don't try this with the clear plastic pens because they will typically crumble. The white plastic cased pens work the best. If you don't have a saw or find it dangerous, you could use a kitchen knife. Take the cap of your bottle and outline the size of the pen barrel onto the cap. Hold the halved pen barrel and trace it with the pen cartridge. Take a drill the size of the pen barrel and drill into the center of the cap. You could also try to use a knife if you don't have an accessible power drill. Take a piece of cardboard or similar material and cut out 3-6 large fins. You will want these to be fairly large because they will hold and support the rocket before take-off.  Look online at rockets for inspiration. You can either use duct tape or use a hot glue gun. Do not use "Crazy Glue" or similar adhesive, as it will chemically dissolve the plastic. Evenly attach the fins so that they are facing down from the water bottle's cap.  Treat the fins like feet for the rocket. The rocket's tip, or the bottom of the water bottle, should be facing the sky. If the fins are uneven, the rocket will not shoot straight into the air. It may veer off course. Typically, the goal is to fly high, not sideways. Take the pen barrel and insert it into the hole of the cap. If there are any gaps you should seal it with used gum or another malleable adhesive.
What is a summary of what this article is about?
Gather the supplies. Prepare the water bottle. Take apart a disposable pen. Saw the pen's barrel in half. Prepare the cap. Cut out the outline. Create fins out of cardboard. Attach your components. Connect the pen.