With this super-engaging kit, children make four real-working electrical devices—and boost STEM skills as they build! The big kit includes more than 30 hands-on components…kids just add simple household items to build a spinning motor, a clicking telegraph, a radio and a light-flashing generator! Plus, the kit comes with a 40-page book featuring easy-to-follow building instructions and tons of facts about each invention. Requires one “D” battery (not included).