Eight fish swim gently in a line. In this Which Fish app, kids must observe the pattern the fish form and select which fish, from a choice of three, to assign to the rightmost position. If they are correct, Quack will respond and a new set of fish will appear. The Which Fish app was designed to teach kids about pattern recognition through self-leveling. If players answer a round without error, they are offered a harder level in the next round. If they do make an error on the way to success, they remain at the same difficulty level for the next round.In this way, the games keep kids within their own comfort levels, nudging them to more challenging levels only if they are ready. The PEEP and the Big Wide World Which Fish? app was produced by WGBH and the producers of PEEP and the Big Wide World. The animated series PEEP and the Big Wide World gives wings to the innovative idea of teaching science to preschoolers. Wry and distinctive visual humor, charming plotlines, and lovable characters combine with a comprehensive science curriculum to attract and engage kids three to five years old. For more exciting PEEP and the Big Wide World content, visit http://www.peepandthebigwideworld.com.