To remain an active volunteer, you have to volunteer a minimum of 2 hours a month, do three presentations/events a year, and one class a year (the staff trainers put on 2 hour classes each month).
I generally take a dog on a home visit at least once a month over a weekend. When we have training camp for the recipients, that's 2 weeks long, I'll take a dog home for the two weeks, and bring them to work with me to get work-place experience.