Making your sessions longer

I've been playing poker for about 2 years and I play reasonably well for approximately the first hour I play each day. Then, I play breakeven for about 30 minutes. Then, my play gets terrible. Maybe I get bored, maybe I start tilting. Thing is, I don't know how to remedy the problem. I try playing more, pushing my limits, but that just leads to losing chunks of the ol' bankroll. I'm still young, and I WILL be going to school, come hell or high water. But I'd like to be able to play poker well for more than an hour...how am I supposed to make money on just an hour a day? Suggestions, anyone?