We purchased this as an add on to the Ball Track Construction Set. But it is a great stand alone activity. The magnets are strong enough to prevent being displaced by the rolling marbles. The pieces are simple, yet allow for creative arrangements. Although our 2.5 year old is still a bit too young to play alone with the construction set, he plays with the magnetic stairs often, making routes, tunnels, getting excited when the balls follow 'his' plan; though they do get stuck occasionally:) This toy will definitely grow with him, and it is great for promoting spatial skills and problem solving.