A quick update--Yesterday the Leotard wanted to use the electric pencil sharpener, but there were no batteries in it:
Leo: God damn it!
Leo: Why does this thing use weird batteries? I've never even heard of M batteries before.
Me: Are you sure it doesn't say double A and it just looks like an M?
Leo: No! It says '4 M batteries'-- Oh. I see what you mean.