PIANO BY NUMBER In this fun music app, kids can play songs they know like Jingle Bells and Twinkle, Twinkle, Little Star on our numbered keyboard. As you play, Mambo the Jumping Monkey jumps to the correct key if you play correctly, but if you make a mistake and play the wrong key, Mambo the Monkey falls down. Each time the monkey falls there are funny sound effects. If you get all the way to the end of a song with no mistakes, you get to meet the Giant Monkey, who has a surprise for you!