Help please...what should i tell him??

there is this group of guys at my school and they sit at the table behind me at lunch, and they always make rude comments to me. they tell me i have nice but they refer to them as "jugs" (idk what that exactly means) and they tell me they want to get into my pants. this is really annoying and i cant sit anywhere else because we have igned seats. what should i tell them?? i tried telling a teacher but they didnt let me sit anywhere else.