Grades 2 & up. Learning that's right on track! Young thinkers can design unbelievable ball track structures via simple, stacking planks. No glue, no connectors -- just loads of constructive fun! Get things rolling by constructing the "Shooting Gallery", "Turbine", "Step Curve", and more! Set includes: 50 pine planks, 2 KEVA® balls, and an idea booklet.