Kmart has a new promotion urging children to participate in its “Indiana Jones and the Kingdom of the Crystal Skull” giveaway. The movie is rated PG-13 “for adventure violence and scary images.” PG-13 means that parents should be aware that it is unlikely to be suitable for anyone under age 13. The movie features guns, an atomic blast, knives, a whip, swords, punches, car chases, insects, and, of course, a snake, and some grisly images, including zombies, corpses, and skeletons. And yet the voice in Kmart’s commercial, urging kids to come into the store and make the purchase that qualifies for a free ticket to the movie, is clearly a child well under age 13. Yes, it is up to the parents to decide what is appropriate for their children to see. But this mixed signals from merchandisers imply to both parents and children that the movie is appropriate and that makes it harder than it should be.