My Problem as of Late

Yesterday we went to MOPS and even got some Math done in the afternoon. Today we got a whole list of great things accomplished. PROBLEM: My daughter usually has a pretty good attitude when I say we are going to write a letter, do math, read such and such book etc. (Okay, that part isn't the problem.) Lately, whenever I ask my son to do something for school, he will rolls his eyes, groan and slouch. I've asked him to please try to have a good attitude, I've tried to explain that life is not all fun and video games.

ONE HAND: I do think I still need to loosen up and be more unschoolish. In my mind I have a set of subjects and activities that we "must" do a little of each day or else we are "not doing it right." When maybe I really need to just be feeding him more things that he will devour and love. Maybe more video game books for him to read or a science fiction book. I know he loves writing letters to his great grandmother about his stories and video games (the poor woman.) But if I try to give him something to read for example, that he has no interest in, then there is no motivation there. And I do, above all things, want my children to get the idea that learning is enjoyable.

OTHER HAND: He does need to learn that we've got to do things in life that are work and aren't always fun but must be done.

What's your opinion?