From Wye Waltz Wiki
This is the ticket for children from 8 to 17. If your 16+ teenager complains, explain to them what a salutory lesson in economics this is.
This ticket does include the Morgan and West, Time Travelling Magicians show, which is worth the ticket price all on its own!
Children thus only require a half ticket (i.e. the non-Ball ticket) and so we're offering these at a reduced rate. We expect that most adults will be attending the Ball, and so it's mostly children who will require these tickets anyway.