Incredibly Interconnectable Toys Kadu Classic 250 Piece Classic Set - Stem/Steam Building + Construction Toy, For Open + Imaginative Play Ages 5+Kadu Is A One Piece Building Toy That Opens The Path To Unlimited Building Potential. Each Piece Connects To The Other Intuitively. Build Anything The Imagination Creates From 2D Mosaics To 3D Models. Each Set Comes With A Range Of Colors Giving Even Another Layer Of Fun. Play And Learning Come Together As A Perfect Match For Ages 5 And Up. The Younger Builder Works With Colors, Shapes And Coordination. While More Advanced Builders Develop Stem Skills