A child who can already name a dozen dinosaurs has usually outgrown the plastic toy version faster than the adults around them realise.
Small, inexpensive fossils — a shark tooth, an ammonite, a piece of amber — are widely available and are not toys. Handing a child something that is actually millions of years old does something a plastic figure cannot.
A small excavation kit, where a real or replica bone is set in plaster or clay for the child to dig out themselves, gives them the discovery moment on repeat, on their own schedule.
A dinosaur-obsessed child is often more interested in what is genuinely known than in a story. A book built around real fossil photographs and honest "we do not know" answers respects that more than a picture-book retelling does.
Look specifically for one about how fossils are found and dated, rather than another guide to species — it is a genuinely different angle most collections are missing.
If there is a natural history museum within reasonable reach, yes — repeated visits to see real specimens beat a single big toy.
Part of our guide to Gifts for one obsession.