The St. Louis Science Center, in collaboration with the City College of New York and the Science Museum of Minnesota, will combine their considerable expertise with youth programs to create new opportunities for after-school STEM learning. Teens, ages 14-17, currently participating in the "Youth Exploring Science" program at the St. Louis Science Center and the Youth Science Center at the Science Museum of Minnesota will receive intensive training to prepare them to assume the role of lead designers of Learning Places that will be created in nine-after school programs in St. Louis and St. Paul. "Learning Places" are educational environments supported by hands-on activities and innovative strategies that integrate science, mathematics and technology into after-school programs. In the final year of the grant the project will be disseminated to five museums across the US including the Pacific Science Center (Seattle, WA), Headwaters Science Center (Bemidji, MN), Explora (Albuquerque, NM), and Sciencenter (Ithica, NY). Youth program staff, and staff and administrators in after-school programs and partnering museums will also benefit from training and professional development. Deliverables include 27 "Learning Places," a teen training program, a Resource Guide for implementation and research contributions to the field.