Barnes & Noble Corporate (no, I don't have any affiliation with them, but I am friends with a regional manager) has mandated that all B&N stores MUST hold a Yule Ball on Friday, December 9th in their stores!!! So, get your costumes ready and go have some fun!
From their website:
Harry Potter Magical Holiday Ball With Barnes & Noble
Friday December 09, 2016 7:00 PM
Dress like your favorite Harry Potter character, wear your holiday best or come as you are and join us for dancing, music, activities and giveaways.