You want the kids to learn to love theater; you want to stimulate their pliant young minds with something more interesting than the usual children's-theater fare. Most of all, you'd like them out of your hair for a couple of hours while you enjoy a grown-up play. The Boulder Ensemble Theatre Company is offering on-site theater classes led by artists for grade-school-aged children during certain of this season's performances. Everyone has a good time, and the entire family gets to talk theater afterward.