June Cleaver’s YA Book Blog BOOK REVIEW MATRIX
Assigning a book one of the following ratings isn’t necessarily a value judgment on the book, nor does an “R” rating in one category mean that the book is without value.  It’s more about giving people a look at what they’ll be finding in any given book, and allowing them to judge accordingly.  Like the MPAA assignments, these ratings are not implying that "G = Good" and "R = bad", but rather that some topics are better for older readers.  Generally, you can assume that G = suitable for everyone; PG = suitable for 4th grade and up; PG-13 = suitable for middle school readers; R = best for high school.  Assuming that NC-17 content wouldn’t actually be marketed as a YA book, our ratings use the following rationale:
Language:  G rating = absence of any kind of expletive. PG = mild swearing, specifically “damn” or “hell” (possibly “bloody”).  PG13 = any other expletive not used in a sexual context.  R = Unlike the MPAA, June feels that the "F" word deserves an automatic R rating, even if used in a non-sexual context.
Nudity:  (For our purposes, nudity in a YA book would also include both lack of, or removal of, clothing in the course of an encounter.) G and PG = nothing. PG13 = descriptions of the opposite sex in revealing attire, including swimsuits. R = removal of clothing whether in a dream or an actual encounter.
Sexual content:  G rating = no sexual content. PG = kissing, if it is more than a peck on the cheek; hand holding; arm around someone else. PG13 = French kissing, especially that described in detail; sliding of hands into another person’s clothing; “grinding.” R = removal of clothing during the course of making out; current consensual sexual activity, implied or explicit.  Rape is considered separately, as an act of violence. 
GLBT content:  G = not mentioned. PG = Mentioned in the context of peripheral characters’ being involved in such relationships. PG13 = Main characters involved in such relationships, but not a main focus of the story.  Also, ugly behaviors such as bullying and gay-baiting.  R = Main characters dealing personally (and explicitly) with these issues.  Violence toward gays.
Violence:  G = no violence. PG = hitting. PG13 = involved hitting or brawling; killing aliens, or anything that goes “splat”. Use of weapons, but without resulting death (especially if a teen is the one with the weapon). R = violent use of weapons, including cutting off of heads or slaying zombies or other aliens; use of weapons involving an actual person getting killed.  Torture.  Rape.
