What's so great about Bach?
Johann Sebastian Bach (Getting to Know the World's Greatest Composers)
Sebastian Bach, The Boy From Thuringia
Johann Sebastian Bach: The Boy Who Sang in the Streets
The Best of Bach: Classical Kids
Bach: Greatest Hits
The Very Best of Bach (free with Amazon Prime Streaming)
Glory to God Alone (documentary) -- free with Amazon Prime
Bach's Fight For Freedom (a favorite movie for kids!)