How can I help my son enjoy math?

It might help him to enjoy it more if you can teach him to think of the math problems as a puzzle game. This is what I do with my step-daughter, who's also 10, when I help her with her homework and school work. If he can see the problems as puzzles to solve, it becomes fun as opposed to seeming like drudgery. You can ign points depending on the difficulty of the type of math he's doing, and have small prizes that he can work toward.