See, there's five stages in your AmeriCorps year - Forming, Storming, Norming, Performing, and Adjourning. This is from a guy called Bruce Tuckman who originally wrote it to have to do with team building - and every AmeriCorps member is part of at least one team.
It's really easy to get stuck at "storming". Trust me. I've been there. Your living stipend sucks, you spend all your time doing inane things when you really signed up to change the world, and your site supervisor/program director thinks you're a moron (or vice versa). The little things are really starting to get you down, and you're thinking about quitting.
Don't quit. You want that education stipend, and you won't get it if you quit. You also won't get the chance to challenge yourself, push your own boundaries, and really discover what you can do. Frustrated? Vent. Call your program director and tell them what's on your mind. Start your own blog. Vent to me here - I'd love to hear your frustrations. What you're feeling is completely normal and part of the process.
I'm telling you from my perspective as a second-year member - it's worth it. Stick it out. If you've quit everything else you've ever tried, stick it out. If you're so broke you're looking for coins in the couch cushions to buy a loaf of bread, stick it out. You CAN get through - and you WILL be proud of yourself. You deserve it. See your year through.
ETA (4/8/09) Some of the comments have expressed a desire for a forum.