Had a good one that I have to share.
DS has been continuing his interest is math (add, subtract) in various bases. Binary and hex are his favorites, but basically he'll do math operations in any arbitrary base... Had to explain to him that base one google would be tough because we'd run out of symbols
At any rate, I figured I'd show him a little bit about converting between bases to help reinforce the idea that they are equivalent numbers, just different representations of the same
value. I showed him the mechanics of converting from a given base to base ten by using powers... (e.g. 2^3 x 1 + 2^2 x 0 + 2^1 x 0 + 2^0 x 1 converts binary) Binary is easy because he knows his 2 "powers" up pretty high. Then we did something in base 3 and he seemed to get the mechanics of it pretty well. Then he said--and this is what I thought was the really, really cool--he said "okay, I want to convert from base 10 to base 10 to see if it's congruent." At first I thought I misheard him! In this sense, congruent is actually a reasonable word to use.
So he then worked out how 231 is equal to 2 x 10^2 + 3 x 10^1 + 1 x 10^0. (he needed a little help, but he was darn close).
Later he wanted to do something in base 11, but melted down and went to bed with only having half a dinner
so no dinner-time math.
But still. Love the math and vocabulary.
JB