Toon Town and Math
My youngest son is, as he will proudly tell you, “five and three-quarters” years old. The son of two math geeks, and the younger brother of two more, he is unsurprisingly also a math kid. Of all my boys, I think he is the one with the strongest mental math skills.
He likes to play Toon Town. He has recently earned a “whole cream pie” gag, which does 36 points of damage. He’s home sick today. He has been figuring out how much total damage various numbers of cream pies can do. He just came and told me, “Tomorrow, I’m going to tell my teacher that I know how much 6 x 36 is!” I asked him how much it was, and he correctly answered 216. A few minutes later he told me that he knew how much 9 x 36 was, and again gave the correct answer. Who knew how much computation Toon Town could inspire?! I asked if he knew how much 10 x 36 was. He again answered correctly, but hesitated just long enough that I knew he was adding another 36 to his previous result, rather than using the usual trick for multiplying by ten.
I pointed out that the easy way to multiply a number by 10 is to just add a zero to the end. He replied, “Yes, but I do it the old-fashioned way!”
Meanwhile, his mental math is so strong that he has little interest in the standard pencil-and-paper methods. He missed the lesson on “borrowing” yesterday, having vomited just before math time. So I showed him at home. He was willing to listen, because he knew that it was what he had missed at school, but he doesn’t like the method. He much prefers what he considers to be more intuitive mental math methods. For example, to compute 34 – 16, he will do 34 – 20 = 14 and then add 4 since he subtracted 4 too much originally, to get the answer of 18. I know that the “fix” is to give him numbers large enough that he can’t do the subtraction using his mental math methods, but for the moment I’m just enjoying watching the little gears turn. 😉