I hate the unwritten, unspoken, underlying curricula in schools that often oppose what we're explicitly told. Supposedly, we're there to learn about what's in class syllabi and state-mandated requirements. We're told that those of us who are educated get further in life. But we also learn, for example, that it's the guy with the biggest muscles who really wins. It's completely contradictory to what we're told. I feel like I got shafted in a lot of ways.
I also hate that those of us who deviate from the mean are punished, in a sense, for not being in the same place as everyone else. Special education is humiliating because if you're in it, everyone knows about it. If you're ahead of the curve, you don't get to work ahead of the rest of the class unless you have a sympathetic teacher; instead, you're stuck regurgitating what you already knew for the rest of the class's sake. And you pay for it dearly, on the playground and in the classroom. Nobody likes a know-it-all.