As a 5-10 year old, the books I remember liking the most were on the outer planets, with high quality full page photos of the planets and their moons. Closer to photobooks than books on the solar system targeted at children. One book was just images of the moons, mainly focusing on Saturn, I used to just look at the images and admire them even if initially I didn't quite understand the details. Most of my physics reading came from random sources on the early internet.
As a 12-13 year old, Stephen Hawking's A Brief History of Time and The Grand Design were by far my most memorable reads, although I already had my developing interest in physics by then.
As a 12-13 year old, Stephen Hawking's A Brief History of Time and The Grand Design were by far my most memorable reads, although I already had my developing interest in physics by then.