Introduction

Marshmallows are for more than just dessert! Burn some after-dinner calories and learn about the science concepts of force and motion, too.

Objectives

To create a catapult and compare projectile objects 

Materials

• Rubber bands (7 or 8)

• Wooden craft sticks — the wider ones work best (9)

• Plastic spoon

• Projectile objects — marshmallows or other small objects safe to launch

Procedure

Take seven of the craft sticks and tie a rubber band tightly around each end so all seven sticks are bound together. Take the remaining two sticks and tie a rubber band on one of the ends. Try to tie the band close to the edge of the sticks. Insert the seven sticks banded together through the two stick bundle. The closer the seven stick bundle gets to the end of the two sticks where they are banded, the more leverage the catapult will have. At this point it will look like a see-saw. Tie a rubber band in a cross fashion, joining the two pieces. Use a few rubber bands and attach the plastic spoon on the end. Place your marshmallow in the spoon and launch!

Conclusion

Compare the various objects you launched. Do heavy or lighter projectiles go farther? Sling large and small marshmallows. Was there a difference? A catapult uses stored energy to hurl an object. The three primary energy storage mechanisms are tension, torsion, and gravity. The catapult was a very effective weapon during ancient times. Need more help visualizing? Watch the video!