The museum as a magical building full of all the interesting things that have been locked away was fun, and overall this is well-written mid-grade fiction. The anti child protective services message, however, was hammered at again and again, too blunt to be pleasant. I think it's trying to be about helicopter parenting, and why that's a bad idea, but the "Gaurdians," who can take children into "care," a terrible orphanage where the children are chained to their beds, become the primary antagonists, not the overprotective parents. I'm not at all sure I love a book that is expressly about fear mongering surrounding social work and child protective services.