Summer Enrichment Program

Simple catapult testing built using 8 popsicle sticks and 2 wooden craft sticks.
Simple catapult testing built using 8 popsicle sticks and 2 wooden craft sticks.

Last month we were asked to do a STEM (Science Technology Engineering Mathematics) related activity with the Summer Enrichment Program at Gobin Memorial Church. It’s a great program which provides positive interactions for at-risk kids in Putnam County. Their goal was exposing these elementary aged kids to a STEM activity; I also wanted them to make something that they could experiment with at home.

We originally looked at doing something with Brushbots, but it turns out those kits are hard to find now & pricey. For Castlemakers Kids we built our own from scratch, but didn’t have enough pager motors on hand & ordering in bulk would take too long. So I settled on making catapults using wooden craft sticks and rubber bands.

There’s a lot of different craft stick catapult designs, but we went for simplicity. Had to, there were more than 60 kids in two sessions – plus only around an hour to build them. The large range of ages, 2nd through 6th grade, meant some would get the ‘lesson’ and others would have no idea what I talked about, but at least they were exposed to it!

Testing an alternate design which uses a stronger spring.
Testing an alternate wooden stick catapult design which uses a stronger spring.

After dropping a few names, like Galileo & Newton, I explained the basics of a lever using a see-saw example. Also mentioned Newton’s laws and apples falling from trees; then told them they were to decide which would hurl further – a marshmallow or a grape. This craft stick design can provide fairly consistent force input since everyone pretty much pulls it back all the way (who doesn’t want to launch it the furthest!).

The kids each build a catapult with 6-8 kids and 1-2 counselors helping at each table. It worked well, especially considering there wasn’t time to coach the counselors first. Everyone involved certainly had fun and when they’re exposed to levers and Newton in a more academic setting they will have heard of it. Lessons learned: Grapes have more mass than mini-marshmallows but don’t go as far & the model I made with a binder clip (stronger spring/more force) definitely shot things further. Mini-peppers… well things were degenerating at that point & we ran out of time.

We didn’t have enough bottle caps to glue on the throwing arm (they still work without them), and several of them were going to add when they got home so they could launch more. I also brought one with a longer lever (2 craft sticks), hopefully a few of them made those at home!

Leave a Reply

Your email address will not be published. Required fields are marked *