Questionable ending (spoiler)
I thought that the actors/actresses gave strong performances but the ending of the movie was very questionable. Several times during the movie, the characters mention that at the time of the murder, the girls were 10 years old and the boys were 12 years old. In one of the final scenes, the main character points out that the rapist/killer attacked his first victim when he was only 12 years old. Although it's possible, it's highly unlikely that a 12-year-old boy would have gone through puberty by that age and be physically able to have sex. If we were talking about 13-year-old boy, it would be much more plausible.
Although children grow up much faster socially nowadays, I doubt that the onset of puberty occurs at an earlier age than years ago. Since the author is a woman, she may be unaware of the physical development of boys. Maybe she didn't realize that just because a 12 year old boy is attracted to girls, doesn't mean that he's physically able to engage in sexual activity. Or maybe the author was trying to purposely misdirect us so that we wouldn't suspect that character as the rapist/killer. Whatever the reason, the author's frequent references to the age of the rapist/killer detracted from the overall movie.