There are several small gift shops scattered throughout the Natural History Museum, but the one at the main entrance, near the parking lot and ticketing booths, is the central location with a superb selection of books, science kits, crates to dig out your favorite rocks and gems, jewelry, books, educational supplies, like DVDs and reading materials on how cow poop saved L.A. and how biologists map DNA and postcards of upclose critters, skeletons and dinosaurs — the usual suspects one would find at a natural history museum. Plus, international and locally made art and designs. Look for the Spark Rock set! If you rub them together they ignite an electrical charge which causes them to glow.