"Dear Mr. Vernon, we accept the fact that we had to sacrifice a whole Saturday in detention for whatever it was we did wrong. What we did, was wrong. But we think you're crazy to make an essay telling you who we think we are. You see us as you want to see us... In the simplest terms, in the most convenient definitions. But what we found out is that each one of us is a brain..."
I love this! The way Remus tries to be polite but insulting, the way Sirius doesn't care what Snape thinks, the way James tries to be polite but then ruins it, and finally the way you can tell that Peter would be whimpering at Snapes feet if this was happening in person :3