A shelf of robot books, not a course in robots. Pick the one that fits your child's age and their taste and stop there. Any single book here satisfies the whole thing. Six of them are stories. Two are fact books that explain how the machines actually work, and that difference matters more than it looks like it does in a shop.
Here's the thing nobody tells you at the shop. 'A robot book' is two different objects, and they sit on the same shelf looking identical. Six of these are stories, with a robot in them, and they read aloud and have an ending. Two of them, the National Geographic reader and the DK findout!, are reference books. They have no plot and no ending, and if you bring one home expecting a bedtime story you have bought the wrong thing. You may want both. Just know which one you're picking up. So: read Boy + Bot and Clink to a small child on your lap. Hand Ricky Ricotta or the National Geographic reader to a child who's just started reading alone. For eight and up there are four, and they're different books. Frank Einstein is the funny one with real science in the margins. The Wild Robot is the beautiful one and the one that will make them feel things. House of Robots is the fast one for a child who says they don't like thick books. DK findout! is the one for the child who's stopped wanting robots to have feelings and started wanting the diagram. Take one. You don't need the set.