Choose any Broadway musical and research it.
Uncover the significance of the show on the outside world.
Maybe it was significant based on what was going on in history at that time.
Maybe it’s significant because of the way it changed the way musicals were done from that point forward.
Most musicals have their own websites with information on them.
Once you have decided on a musical, you can look for their official site online for more information about that particular show.