How do I get this guy to like me(want lots of answers)?

I really like him, but i know he doesn't like me. I used to be able to get any guy to like me butnow i just can't. And its because im trying to get a guy whos 'untouchable' (not in a dirty mind, im only 11) and dont comment about my age. its my generation and me. i cant help it. i thought about singing a song in the talent show next year to him telling him how much i like him but also how i feel. do you think its a good idea? if not, what should i do?