Have you put enough thought into the movies you allow your kids to watch? The story behind a film’s rating lies much deeper than that rating. “Not all PG-13 films are created equal, in part because there are so many of them: Behind R, it is the most popular rating,” said Dr. Peggy Drexler in The Huffington Post. “The Motion Picture Association of America has [an] incentive to label films PG-13. The more people who can see the film, after all, the higher the potential profits.”

But PG-13 is wildly inconsistent: Some films’ “mature themes” translate to little more than subtle innuendo that might fly over a child’s head, while others show the mass destruction of entire civilizations.

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“Parents get confused,” noted Drexler. “In cases where kids have done well with one PG-13 film, parents may consider them mature enough to handle all PG-13 films. Or they may ’round down’ and assume that if it’s OK for a 13-year-old, then it’s OK for an 11-year-old, or a 10-year-old … or maybe a 7-year-old who ‘won’t get the dirty jokes anyway.’ It’s a slippery slope.”