I'm having the exact same problem today... Some girl told everyone lies about me and they compleatly ignored me and laughed about me behind my back. But people at you're school are dumb ass holes who are always mad so they just let there anger out on everyone and feel like there the best in all... So don't be sad, be proud that at least they won't have a reputation and you will because of how they are acting. Everyone has to be a little different. I dont know if that made sense at all xD