My name is (your name) and I am a student at East Palo Alto Academy High School. I am contacting you because I would like to find out more about the possibility of volunteering at your organization, (name of organization). Would please share with me how I could volunteer and what dates and times you need someone to help. Please let me know the details.
After hearing your response with the needs at your organization, I will respond with my decision. Thank you for your time and have a wonderful day!