My son went to Blue Skies Montessori for 2 years (ages 2-5), and loved it. The staff is warm, and has little turnover. I think they prepared him well for Kindergarten in a low-key way that made learning fun for him. We just went back for the annual potluck, and my son was so happy to see his teachers and old classmates. They are open to having you sit and watch while considering placing your twins there. I talked to the owner at the party, though, and she said they are pretty full up at the moment. But I know several kids who are graduating to kindergarten, so there might be space.