For me, there wasn't much to like about school. Through junior high, high school, and the first year or so of college I learned to dislike writing assignments more and more. I was fascinated to notice, however, that a few years later I was finding things I wanted to say -- and I was enjoying both saying them as best I could, and learning to say them even better.

A few months after graduating from college I was working as a research assistant and had occasion to take a class in computer programming. To my surprise, I enjoyed the whole thing. It occurred to me that it was probably the first class I'd taken where there were no grades, no deadlines and no pressure, and I was there only because I wanted to understand the subject.

Unfortunately I have no advice for how to get from hating school and classes to enjoying them. I could probably have gotten there more easily than I actually did but I haven't a clue how, nor (perhaps more important) what else it would've cost me.

Fwiw, I once found myself thinking that there were two activities that were definitely not part of my self image: riding a motorcycle and writing a thesis. At the time I had that particular thought, I was riding home on my motorcycle after submitting my (undergraduate) thesis.