Ideas for Daughter's 11th Birthday?

My daughter turns 11 in early March and is 50% girly 50% tomboy. She wants to do something active like flip out, but lots of her friends have already done that. It's just a small party with her and five other girls. She thought the Crocky Trail would be fun, but it might be too cold. She really wants it to be memorable and special. We thought about escapism, but that only takes 5 people per room, there's 6 of them and she doesn't want to split up. We live on the Wirral so there aren't a lot of hotels or venues near us (in West Kirby). I could really use some ideas!