CHEERLEADING OPINION.. need help!?

i am a cheerleader, i have been since 1st gradee but i also do tennis and softbal. so i consider myself athletic, but people think im ditzy and stupid. while guys think that i'll be easy and they think im hot and just tell me that to my face. just because im a cheerleader doesnt mean im stupid or easy for guys to get at. i have straight A's in all AP courses and i hate it when guys treat me like a trophy, they act really nice untill i start dating them, then they want to treat me like a piece of meat. what do i do?