This Marbles and Blocks marble maze set by TEDCO is by far THE BEST marble maze out there. Building a maze with this requires creativity, thinking, and problem solving, but even young children are able and fascinated by it. It's a bit spendy (especially if you are comparing it to the plastic alternative) but so worth the money.
This set has been sitting on our floor for the last week and children and adults have been having a wonderful time making different paths for the marbles to travel. Here's one creation by a child:
Ginger Carlson, author Labels: blocks, marbles, mazes, parenthacks, toys