Lego Club Challenge–Cantilevers and Weights

This one is another classic STEM challenge I repurposed for Lego Club.  After going over rules, I showed everybody a picture of a diving board, a crane, and an airplane wing.  Then I asked everyone what they all had in common.  An older kiddo eventually guessed that they were all cantilevers, which means that the structure is only supported on one end with the other side kinda free.  So the challenge today was to build a STRONG cantilever, because at the end we would put WEIGHTS on it!!

Lego Cantilever 1

I found a good, cheap weight set on Amazon, which was great since these can get super expensive.  It had two big weights in them and a bunch of small ones.  The great thing about Legos is that they can hold up to a lot of stress, so it doesn’t take a whole lot to build a functioning structure.  BUT that also means you’ll need some bigger weights to break these things.

Lego Cantilever 2

So I let kids build for about a half an hour, then I started coming around with my weights to start testing.  These weights were in grams, so it was a great opportunity to talk about grams and converting into pounds.  Kids LOVE adding more and more weight until they can’t take anymore.  Then you can talk about ways to maybe make their structures better.  Or they can just decorate them.  I got a lot of pools since they looked like diving boards 🙂

Lego Cantilever 3

So that’s it!!  At the end we went around and tested together one last time to see everything break.  One of my kiddos was almost able to hold the whole weight set of 2000 grams, which is over 4 lbs!!

Lego Cantilever 4

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