Question: what questions to ask a volunteer?
Answer: What are my interests? ... 
What are my skills? ... 
What do I most want to learn from the experience? ... 
What will I gain from volunteer work? ... 
Will my volunteering affect my other commitments? ... 
How flexible am I? ... 
How much time do I have? ... 
Do I want an ongoing assignment, a short-term assignment, or a one-time assignment?