1. Make the cart.
Measure a 1.5 inch border all around the rectangle. » Cut 4 slits along the border lines. »Fold up the edges of the paper to make a box. » Secure the shape with tape. If using a milk/juice carton, just cut off the top of the carton to create your cart.
2. Attach the straws
Tape two straws on opposite sides of the inside of the paper box. » Pin a safety pin across the top of the straws. » Slide the third straw through the center of the safety pin and the two straws.
3. Attach the cart to the track.
Thread the string through the third straw. » Tie one end of the string to a sturdy place.
4. Attach the balloon.
Blow up a balloon. » Twist the mouth piece so the air doesn’t come out. You might be able to use a clothespin or a paperclip to help you keep it closed. » Tape the balloon to the third straw. Make sure not to bend the straw or else it won’t slide along the string.
5. Launch the cloud trolley
Hold on to the other end of the string and make sure it is taut. » Release the balloon. If you pinched the mouthpiece, remove that so the balloon can shoot along the string.
Your safety is your own responsibility, including proper use of equipment and safety gear, and determining whether you have adequate skill and experience. Power tools, electricity, and other resources used for these projects are dangerous, unless used properly and with adequate precautions, including safety gear and adult supervision. Some illustrative photos do not depict safety precautions or equipment, in order to show the project steps more clearly. Use of the instructions and suggestions found in Maker Camp is at your own risk. Maker Media, Inc., disclaims all responsibility for any resulting damage, injury, or expense.