San Mateo County Active Access
The Active Access Initiative is a collaboration of San Mateo County, local recreation departments, and non-profit community partners. Our mission is to promote healthy physical activity in the community by offering you, the residents of San Mateo County, free and low cost (less than $5 per class) physical activities in the city where you live.
Check out http://www.smchealth.org/ActiveAccess for activities in Foster City.