Arrow X when I was your age I had the same problem. I did awesome on tests but I almost never did homework (and when I did it was usually durring lunch right before class started). I got out with a C, but I could have gotten an A. And not a day goes by where I don't wish I tried just a little harder.
I know you're good at math and we're proud of you son, but we want that teacher to feel that same pride we do!
