DS 5.5 does the calculations in a really different way from myself. He was doing his homework, like 36+28. I had never thought of doing them the way he proposed and it just opened up my eyes to interesting ways of thinking about digits.

At Kumon, where he does problems like 56÷573 he doesn't like to write anything down but rather does it in his head. I can see the "SHOW YOUR WORK" nightmare coming in school...