Takeaway: Fun young adult fantasy novel. There are some serious themes, but they are written in a way that is appropriate for 11 and up.
I have been reading a lot of fairly heavy theology recently. The heavier the theology books I am reading, the more likely I am to need light fiction to offset my brain. I share a Kindle account with some younger people, and they picked up and read the Percy Jackson series last spring. I have not seen the movie (although I probably will now) and did not know anything about the books going into them.
I am a fan. These are quick reads for adults; I do not think I have spent more than 2 or 3 hours on any of them. (I am in the middle of the fourth right now, all in a week.) I also think they are appropriate for kids age nine and up (depending on reading level).
The basic storyline is that Percy Jackson is a bad student. He is always getting in trouble and has ADHD and dyslexia. He loves his Mom, but he knows he is making her life difficult because he is always getting in trouble at school. Eventually, we find out that one of the reasons Percy has a problem is that he is actually the son of one of the Greek gods (a half-blood).
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