Logicly - Lets kids build their own logic setups to see what happens. Start with simple AND & OR gates and try to make the bulb light up, work up to projects like adders. Teaches logic and shows how gates work. . "Simulates the boolean algebra performed by logic gates, which are a vital part of digital circuitry and computer architecture." * This is now a commercial ed app. 30 day free trail ready for downloading. In Challenges, Logic & Probability and Technology.