The object here is to build a catapult and then investigate how changing the configuration of the catapult effects the objects being used as ammo.
Wide wooden sticks (best but you can use lollypop sticks)
Marshmallows (mini and large)
Any other type of ammo you can fit in the plastic spoon
Rulers for each group to measure distance thrown
I find this best run in groups but each person in the group makes a catapult, that way different configurations can be built with the need to take the catapult apart when conducting the experiment.
First let them build the catapult using the instructions provided
Then give each group a set of ammo that they need to experiment with.
Get them to predict how far each item will be thrown by the catapult in the different configurations they have made.
Let them experiment with the catapults and record the results.
Get them to decided which configuration is best.
At the end get each group to report to the rest of the beavers, which configuration is best.