If you need more structure (I do), then I'd definitely recommend that you talk with him about what he wants to do. Do as much of the things he wants to do as you can do. Explain to him that there are certain things that must be done--writing, math, reading, etc.--but that HOW you complete those tasks is open for negotiation. Make an agreement *together* about what school will look like. Get his buy-in by letting him have more say, but then hold him responsible. He might be willing to do 10 problems a day if they're really challenging if he also gets to do something educational that's enjoyable for him.
We have "School Meetings" on a regular basis. The kids love having a certain measure of control in the way they're educated, and tend to work a
whole lot harder when they've agreed beforehand.