9 year old math

So Jordan is in 3rd grade and he comes home today and says, "Mom I'm starting on division in math." Me being the observant mother that I am ask, "You mean you already know multiplication?" He has never practiced multiplication at home so I had no idea he knew it. I quizzed him a little bit to make sure he knew what he was talking about. I started with the more simple problems like 2x6 and 3x4. Then I hit him with a hard one. All of my older children have had problems with their 6's so I asked him what 6x7 was. He couldn't remember so he says, "well 7x3=21 and 3+3=6 so 21+21=42, 6x7=42." WHAT? How the heck did he figure that out. I'm going out on a limb here and guessing that he is not going to be coming to me for math help much longer. Wait, actually I don't think he's asked me for math help since kindergarten. Little smarty pants!