Learning Math with Cards

2007-07-08 05:36PM PDT/Home

Philip Aaronson

Construction My oldest wasn't feeling well, so she and I played the card game war for an hour or two to try and keep her mind off of how crappy she felt. Making things more interesting I asked to tell me by how many she won by on each hand as long as no face cards (or an ace) were involved. So if she put down a 7 and I put down a 5, she'd say, "won by 2". If I won, I'd do it. The difficulty I discovered was that she doesn't yet know all the combinations that make 10 which are really handy. 9+1, 8+2, 7+3, 6+4 and 5+5. Oh and 10+0 as she was quick to correct me. If we hit 9-4, which she didn't know, I was trying to get her to recognize this as 10-4-1 or 10-5 or 5.

The game evolved into me always putting my card down first. Say I put down a 5, she'd pick it up if she won and say, "won by 3". And I'd have to say, "you have an 8!". It never failed to put a smile on her face when I got it right. Like it was magic.

When we got tired of cards, I went back to my desk, and wound up following a link to Enso . It was ironic that that their demo was about using Enso to calculate 4*2.99 using their inline thing. That this was exactly the kind of problem I'd been training my daughter to be able to do in her head, only a little more advanced. Translate 4*2.99 into 4*3 - 0.04, or 11.96.