Here is the response I would use (you can check to see how I commented by clicking on "Comments"):
Since I took Mythology class in 7th grade and I read Percy Jackson and the Lightning Thief this summer, I feel like I have a lot of schema about Percy Jackson and the gods and goddesses in the book. I have also seen the movie two times. I am very interested in reading this book again so I can notice details that I may not have seen the first time I read it.