Tabla de Contenidos: “…Getting to know Greenfoot -- The first program: little crab -- Improving the crab - more sophisticated programming -- Finishing the crab game -- Interlude 1: Sharing your scenarios -- Making music: an on-screen piano -- Interacting objects: Newton's Lab -- Collision detection: asteroids -- Interlude 2: The Greeps competition -- Creating images and sound -- Simulations -- Additional scenario ideas…”