Connex kits can be built and played with individually or connected together. Each kit snaps together and can be taken apart when finished for building another day. A reusable box is included with every kit (for storage and to mount your project); easy-to-follow instructions help the builder to work independently. Projects are translucent plastic, and each kit requires one or two AA batteries (not included). I built the "Spin the Wheel" Kit and had a lot of fun - it worked just like it was supposed to. I like that these kits don't take forever, aren't complicated, and be taken apart and built again.