From Djeco, this set features: Recommended use: ages 8 and up 48 pieces A wooden building game of chain reactions requiring careful thinking. Children can copy the designs in the instructions booklet to build courses, or make up their own  This chain reaction game helps anyone learn how speeds vary depending on the weight of an accessory and how space between elements changes the results. Helps children to understand beginner engineering principles. All the kits in the collection are compatible, for even more inventive action-reaction courses! Imported.