 Each programme followed a broad theme and consisted of songs, stories and activities with presenters in the studio, along with a short film introduced through either the square, round or arched window in the set.The programme spawned numerous spin-offs in Britain and other countries and involved many presenters and musicians during its run.Despite a revamp in 1983 "Play School" maintained the same basic formula throughout its 24-year history, but changes to the BBC's children's output led to the programme's cancellation in 1988, when it was replaced by "Playbus", which soon became "Playdays".