## Thursday, August 25, 2011

### Negative Numbers

A few weeks ago I wrote about Lucas playing with percentages. He was joyfully telling me how full all of his food centers were, during a one on one shopping trip. Do I think because of this one playful moment he has now mastered percentages? No. Do I think he fully understands the concept? No. But the more he plays with it, the closer he gets to understanding and then mastery.

Lucas is not the only one working to understand new concepts in math. Last year for Christmas I bought each of the boys their very own calculators (mostly so they would stop stealing and losing mine). Recently Nico has started wondering what happens when you subtract a large number, from a smaller number. One day, calculator in hand, he comes to tell me, "Hey Mommy, 2 minus 4 is negative 2." That simple operation sparked an interest, and for the last several days he has been subtracting more and more large numbers from smaller ones, to see what he gets. "Did you know 700 minus 900 is negative 200?" he asked me just last night.

Along with negative numbers, the calculators are also helping both the boys to recognize and learn place values. They type in a bunch of numbers, and then have me read it off the calculator for them. Nico came to me last night and asked if 10,000 was 100 thousand. I said no, it was only 10 thousand, and to make it 100 thousand, he needed one more zero. Later he came and asked me what 90,000,000 was. I said 90 million, and he said "Oh cool, seven zeros to make 90 million.

They think they're just playing when they pick up those calculators, but I see it for what it really is.