This is a legitimate classic that earns its reputation. The premise—two kids living secretly in the Metropolitan Museum of Art—is so delicious that it's spawned decades of copycat plots. Konigsburg nails the sibling dynamics, the art mystery is genuinely engaging, and the book sneaks in real learning about museums, art history, and self-discovery.

The catch? It's from 1967, and it reads like it. The pacing is slow and thoughtful, the cultural references are dated (pay phones, 1960s money, no security cameras), and modern kids used to Marvel movies and Roblox may need patience to settle in. It's not unreadable—plenty of 8-12 year olds still love it—but it's not competing with Diary of a Wimpy Kid for page-turning urgency.

That said, if your kid is a reader who likes mysteries, museums, or smart protagonists, this is worth pushing through the first few chapters. It's safe, enriching, and genuinely clever. Just don't expect them to devour it in one sitting.