From http://en.wikipedia.org/wiki/I_Didn%27t_Know_What_Time_It_Was : "I Didn't Know What Time It Was" is a popular song. The music was written by Richard Rodgers and the lyrics by Lorenz Hart for the musical Too Many Girls ( 1939 ). Early hit versions included Benny Goodman and Artie Shaw. The Crampton Sisters 1964 revival for the