I was looking for an example that works with middle-school knowledge of computation but that isn't so trivial as to be meaningless. Implementing exponentiation

I was looking for an example that works with middle-school knowledge of computation but that isn't so trivial as to be meaningless. Implementing exponentiation in terms of multiplication seemed to fit the bill. I could have tried to put in a rough approximation of the rdmsr state machine, but people would have rightfully tuned out in the second sentence.