Marble Run Construction SetYoung engineers will enjoy constructing a run and then testing their design with the enclosed marbles. Simply align the holes and ramps to create a different maze every time! Marble runs promote imagination, experimentation and fosters spatial perception and motor skills. See our additional add ons to give this marble run endless possibilities. Contents: large construction set with 42 beechwood pieces, 6 marbles and a little bell that rings when the