We purchased this big kid marble run last Christmas. Our children never touched it after the first day. It does not work as designed. My husband had to add bean bags to all of the bases to keep them from falling over. The marbles included with the set could not complete the loop. We did have success with lighter weight marbles that we had around the house. Curves had to be adjusted multiple times to keep the marbles on the track. I guess there was some educational value for the kids to try to figure out how to make this poorly designed product work. They needed significant coaching from their engineer father. By the time they got it to work, they had lost interest. It was a waste of money.