We had hard wired online access only for years, up until maybe two years ago. Kids computers were in the kitchen eating area, the only place I gave them online access. We could always see what they were doing, and they almost always went to bed (and off computers) before I did. Now that we have wireless, out of habit they still do all their online work in the kitchen.
My son does online gaming a lot, and that has translated into him working on making custom maps for games, and making his "own" games by modifying existing games (legally! Various online PC games provide the ability to mod the games). Involves programming and using various graphics programs. He will probably be bored with the initial "college level" courses.
Good luck on working this out with your kids. At a minimum, I always insisted that my kids got up in the morning on time (for whatever was going on), and had good grades in school. If they couldn't get up on their own, then they simply had to go to bed earlier, until they could. If grades were slipping, they worked on homework instead of playing on the computer. I do feel that proper sleep is needed for school. No electronics in bedrooms, unless they were doing homework.
It seems to have worked out for us... but it was rarely "easy"! Especially these days, where if you try to limit your kids, or God forbid punish them, you are open to charges of child endangerment and/or a visit from the state child welfare office.
Just because it is a dumb, easily resolved issue, doesn't mean you should stop doing it. - sorry I forget which GT'er posted this...
I'm not angry, I'm just loud. - Friend's son.