How can I get started with helping out my community? Please answer!?

I'm 13, and I really want to help out with my community (San Diego) my school just closed the Cesar Chavez Club, so now there's no way for me to give back. I wanted to help the less fortanute for Christmas, but I just don't know where to get started! I mainly want to do something for animals, but I will also help the homeless, or help clean the enviorment. I don't know! I just want to help instead of just watching T.V. I know there's a group that goes around to different schools and teaches kids how to conserve water (They're all students) So please if you know any organazition to help animals, the unfortanute, or the enviorment, please let me know, and a website/phone number too please!