Par CASEY W. / JACOBS J.. Grease Is Still The Word! Warren Casey and Jim Jacobs' Grease was a popular stage musical about the sub-cultures in 1950s American High Schools and in 1978 it was made in to a feature length motion picture, starring John Travolta and Olivia Newton-John. Subsequently it became a seminal teen musical with its evocative and energetic songs, strong characters and a great stor…