This is a story about our son, Adam, when he was in 3rd grade (he's 26 now).
1995--
The other night at dinner, Adam was acting a little distracted, like he was reading an imaginary book. His eyebrows were furrowed, and I swear, I remember that same look on his face the day he was born. He stood up and said, "I've got to check out a theory, I'll be right back." He came back in a few minutes with a pocket calculator and said, "I was right, any number whose digits add up to 9 can be divided evenly by 9." I said, "What?" and Janet said, "Huh?" Frank said, "That's right, but how did you figure it out?"
He said first he thought of 36 and 63, both could be divided by 9 and added up to 9. Then he thought of all the numbers in the "nine times" multiplication tables: 9, 18, 27, 36, 45, 54, 63, 81...each one added up to 9. Then he tried some bigger numbers: 21,321 and 111,111,111 on the calculator and they too added up to 9 and were divisible by 9!
Janet said, "Hm. Is there more corn?"