Ok seriously i have a few things too say
type childline into the google bar. Sign up there, speak too a counciler. Childline is cool cuz they don't jump too conclusions or make hasty decisions, also ur parents won't know cuz childline NEVER sends emails and it's free.
wear short sleeve tops/shorts so that people see the bruises and cuts or whatever else ur parents do too u. A teacher WILL eventually get suspicious. This IS NOT attention seeking as long as ur not looking for sympathy, it's just telling people that u need help, without words.
The final thing is:
Love life just because people say ur worthless, fat, ugly, a freak or weird, who says there right ?? After u leave ur cruel parents behind, find a passion or a dream too follow and don't ever give up on it. It could be drawing, painting, playing guitar, sailing or maybe even hugging random people it's all cool.
I'm here if u need too talk, just wall me or pm me