Is it Really Too Late?

So I got an opportunity, with Jace's permission, to read his journal he writes in class at school. There were a few entries, some shorter than others. As much as he likes to read (He is currently reading the 7th Harry Potter book), Jace DOES NOT like writing. So I'm glad he makes the effort to write the little that he does so that I can glimpse a little of life through Jace's eyes.

3-5-08
"yesterday I got on the bus and did math. When I got off the bus I went home and did more math. when I went to bed I wanted to do more math but it was to late."

Isn't that incredible? And, just so you know, I AM a nice mom sometimes (when he's in bed early enough) and Jace has the clipboard and paper in his bed to prove it. He loves working with numbers and learning different things you can do with them. But after reading that, I couldn't help but think, would it be so bad to let my child stay up late if he's just doing math to his heart's content??