Fighting=[?

this kid name kid in my school is really annoying && he always make fun of me. The reason why he makes fun of me because im in speech. But it was nothing to do how i talk its with another thing but i dont no what its about. so one day he called me a ugly *** ***** when he's the one thats fat && ugly. And also said talk to me when u no how to talk and i do no how to talk. He always starts with me i dont nothing to him. But when i tell him that he's fat and ugly.... but he never stops im in 8th grade and this is really annoying. He makes fun of evey one even he's friend!! tomorrow i sware im ganna hurt him but im in 8th grade and they ca always say u can gradate. Or i cant go on my trp i and i dont want that to happen. so i dont no what to do. I already have prob. at home i dont need it at school too. And last year i was really bad and i dont wanna be bad agen. so what should i do because im ganna kill this kid!!=[