Complex sentence: He then taught art in two secondary schools, and was Head of Art at Harrow County School for Boys from 1949 to 1960, where he formed a jazz club in which he played his blues records, and also played mandolin in a skiffle group.
Split into simpler sentences: He then taught art in two secondary schools, and was Head of Art at Harrow County School for Boys from 1949 to 1960. While there he formed a jazz club in which he played his blues records, and also played mandolin in a skiffle group.