Kids can start up their on own musical trios with this Rhythm Group of Three. This balanced set of instruments includes a metallophone, a glockenspiel, and a set of simple bongos. Kids can start up their on own musical trios with this Rhythm Group of Three. This balanced set of instruments includes a metallophone, a glockenspiel, and a set of simple bongos. All three of these are excellent on their own, but together they are a great way for kids to learn how to