How can I meditate to fit my lifestyle?

I'm 12 and want to meditate. Sounds unusual right? I go to a public school and am facing problems with friends and stuff like that. But I don't want that to bother me. I want to focus on my school-work and come home in a good mood, which I usually don't. I have read about meditation before and heard it can be helpful for clearing your mind. Is there a good meditation "plan" for a girl like me? Any relaxation music or ways that I can meditate? Any info will be helpful! Thanks!!!