I'm baffled

I bought lots of workbooks for Gordon since last year. He's never shown any interest in them until TONIGHT!! It's the number writing book that started him off. Yes, my boy loves numbers. And so, he went and finished lots of pages on his own. He can write, but of course needs a little bit of help from me. Each time he's not satisfied with his writing, he'll say, "Try again, rub rub rub....".

Is this for real? Will he still like what he's doing now and continue with it tomorrow morning, after school, before bedtime, forever? Gee... if this is really happening for good, i better go buy numbers tomorrow. Yawnnnn.... "Gordon, you finished yet? Mama's sleepy. Very sleepy...."