Since it was free, and it was about everyday science everywhere and teaching people about science, I downloaded it. Because, you know, Science!
I was nodding right from the first two paragraphs of the preface. Do you remember going to some museum, or aquarium, or other educational and fun location, get interested, have a fun time, then at the end of it get asked by your teachers or parents, "what did you learn?"
And then drawing a blank.
The funny thing is, the first thing I thought of when I read that was actually back in university, when halfway through any given class the professor would announce the date of the midterm: my first thought was usually to wonder what he could possibly test us on, we hadn't hardly learned anything.
I don't know if the book answers the question of how to help kids answer the question "what did you learn?" (I haven't finished reading it yet) but it certainly tries to answer the question of how to help people learn and absorb and integrate science more effectively.
Personally I think instead of asking what they learned, you should ask your kid what were some of the cool things they saw. They'll probably surprise you with the amount of stuff they learned. (I saw a deer with fangs at a museum once. That was seriously weird.)