This paper describes an algorithm which allows singing to be analysed in real time using a PC and then re-synthesised by the computer using whistled notes. The singing can also be transcribed as a series of notes on a musical stave using a MIDI file as interface. Pitch amplitude and spectral change parameters are derived from the input waveform. A sequence of musical notes is derived from a set of parameters using a set of rules. The system is designed as an entertaining, yet educational tool for children, and will be embodied in an interactive multi-media system. In its electronic form the paper has attached files demonstrating the results of the re-synthesis algorithm.