Slumber Party. Caramel popcorn, ice cream sandwiches, floats, candy, chocolate, etc.
Knock off famous books theme, like Barry Trotter, Slurlock Houses, Spylight, Alisha In The Mirror, etc.
Different mythologies OR different countries' takes on 'universal' stories. Like have Africa's, China's, Peru's take on Cinderella as well as the Perrault &/or Grimm versions.