** spoiler alert ** Here's major spoilers so don't read if you don't want the book spoiled.

Josh felt guilty because he thinks that while he helped with Miss Sherman's project for her master's degree, they slowly fell in love and startred a sexual relationship.
The truth is, Josh later finds out that there never was any master's degree project! Miss Sherman decided on the first day of school that she wanted to sleep with Josh, so she made up the master's degree project as a way to spend private time with him and a way to get him over to her house. That is when he finally realizes that this "affair" was NOT his fault and he was just a kid and Miss Sherman was a calculated and predatory child molester.

Also, just my opinion but I think it's dumb when people say it's "women-hating" or something because they made it like Josh's abuse was caused by his mom going back to work. I don't think it is about women or mothers. I think it is really about parents in general- a LOT of kids get abused by "trusted adults" who step into the lives of these children because they see that they will have the opportunity to abuse them because they're alone more. When kids are alone or their parents are busy, there is more opportunity for other adults to step in and hurt them. That's just the way it is.

I loved this book but the baseball parts were boring, and I think that the whole rachel relationship was unrealistic and silly.