Right now through Plum District they are offering one month of Gymboree Classes for $49 (usually $125). It is available at multiple locations in the California Bay Area.
The classes are separated by age group. You can check here: http://www.gymboreeclasses.com to see what times they have or which ages.
I like it because they have classes every day and at different times PLUS you can go to the drop in play time too!
When checking out at Plum District, use promo code: visa10 to get an additional 10% off...making the total $44.10 (instead of $49).