A few weeks ago, Simon’s pillow talk was an attempt to add two three-digit numbers. He asked me what 120 plus 120 was, and when I asked him to try to solve it himself, he came up with 140. When I reminded him that he needed to add the ones and then the twos, he got it right. Then he blew the next problem.
Still, the attempt was there, as was some understanding of place value. So a couple of days later, just for the heck of it, I drew up grids and filled them with three-digit addition problems. I explained how the columns were ordered, showed him how to go from right to left, and worked a few. Then I let him loose with about five more problems. He nailed them. So I got rid of the lines and added the plus and equal signs. He nailed them, too.
Then he decided to write out a problem himself. As he’s five, he didn’t understand that each column needed to add up to 9 or less. Also because he’s five, he would take no direction from me once he decided that he wanted to do it himself. Then he got going, immediately came upon an 8 + 2 column, and sheepishly wrote 10 at the bottom of it.
“Simon? Does 10 fit there? I asked.
“No, it really doesn’t. I don’t know what to do!”
“Well, I can show you, but your head might explode. What do you think?”
“I want you to show me.”
So I explained the place value of each column to him, guided him to put the 0 on the right and carry the 1 over the middle column, and then told him to add the two left-most columns, including the one that now had three rows in it. He got it. Then I asked him to read the problem out loud to me, which he also got.
Then I asked him what he thought. He laid his head on the kitchen island in an exhausted heap. A few seconds later, he raised up, put his hands on either side of his head, and made exploding noises. I laughed out loud. Simon shared the laugh and then asked me to show him how to add four-digit numbers.
His head might be exploding now, but if he keeps this up, it won’t be when he hits calculus the way mine did. And I have to say, if Simon were going to choose areas in which to be unlike his mother, lover of math and player or sports are two extremely good choices. I hope both of these affinities stick around for the long haul.
Carrying over at five?! Wow.