A couple of fun reads about astronomy are the "George" series by Steven Hawkings and his daughter. (George's Secret Key to the Universe and George's Cosmic Treasure Hunt)
DD8 tore through them, loved the photos and when we went to a local star party asked one of the retired astronomy prof's there all sorts of good questions that she came away with. I
I don't know who came away more impressed - DD because the man not only knew the answers to her questions but was very willing and able to discuss them with her, or him because here it was in the middle of a field and he is being quizzed by a then 7 yr old about some of the newest ideas in astronomy. (I wish I could have seen his expressions more smile )