Renaissance Adventure Guides doesn't have any scheduled playboating classes, per se, but they do offer private lessons both at the pool in Golden and in the CO river (one of the few that still has water and decent beginner play spots) that can be tailored to playboating. They have a few instructors that are fantastic playboaters. Of course, if you want to get a group together to bring the cost down, that could be a good way to go.
Other than that, there will not be any scheduled playboating classes here in CO until the June competition circuit (Paddlefest, Teva, etc) rolls through the state. Usually there are some playboating clinics held around that time.