Connect wall and floor panels to build your structure;Use the modular building pieces to create chair swings, staircases, revolving doors, and more! 51 piece set includes wall and floor panels, building pieces, connectors, arches, wheels, and more;Teaches important STEM skills: hands-on problem solving, spatial and fine motor skills, self-confidence, and creativity. Compatible with all other Roominate products and encourages open-ended play for endless possibilities.