Kids ages 3 years and older can build their own post office again and again! 35+ pieces, including wooden track pieces, links, characters, and accessories 2 ways to build! Create a track or building using the same pieces Follow the guided instructions or make your own designs! Collect additional Wonder Builders destination building sets, expansion track packs, and vehicles (Each sold separately and subject to availability) With this Wonder Builders building set; kids can design and build their own Special Delivery Depot post office; where they can slide packages down the mail chute; load them onto the truck; and send them out for delivery! Using the 35+ reconfigurable play pieces; preschoolers can mix and match different designs using the same pieces to make the building or connect into tracks for the vehicle. With so many combinations to explore; kids can make a different post office again and again-there's no wrong way to play! Where development comes into play -- Creativity & Imagination: Kids can let their imaginations run wild as they use creative thinking to design the post office and tell stories with the characters. Engineering & Building: As preschoolers build and re-build the Special Delivery Depot; mixing and matching the play pieces to create different configurations; they'll practice their designing and building skills!