Kids build a twisting, turning marble run and race incredible glow-in-the-dark marbles! This construction kit features 10 sturdy bases, 55 action pieces, and 135 smooth-run tube pieces to make endless configurations possible.The six different colors of glow-in-the-dark glass marbles can be recharged quickly with the UV light. Marbles can easily be stored when not in use with the mesh bag. Learn about motion and gravity in the detailed learning guide and experiment with different marble run builds to make the marbles race faster or slower.