I vaguely remembered reading this one as a middle schooler, but very little beyond the title. I'm really glad I picked it up again. It's a simple, but cute and adventurous story that is something of a toned down version of Night at the Museum. Claudia is the perfect angsty preteen and I loved the balance between herself and her brother. Reading about all of the displays and interesting items in the museum also makes me really want to visit and see it all for myself. It's always seemed such an intriguing place, but this novel really brings that to life. The added aspect of Mrs. Frankweiler made things nicely tongue-in-cheek and provided a great addition to the point of view and made the story have a little more levity. A great middle grade read.