Girls as young as 12 are using photo-sharing site Instagram to post pictures of themselves to ask its 100 million users: "Am I hot or not?"
The alarming news of the cyber beauty contests has been revealed by the Washington Post, which says youngsters compete for the most 'Likes' for who is the 'prettiest'.
There are no prizes, except for the most Likes but the losers get a big, red X slapped on their photos or the word 'out' scrawled across their faces.
Parents are concerned that kids are risking their safety by putting information up for strangers to see - and also leaving themselves open to horrible comments.
The hashtags #beautypageant returns 10,508 photos, #hotornot 14.616 and #amipretty over 5,000. They contain screen after screen of young women: Some are professionally airbrushed modelling shots, others show very young gap-toothed children posing against a backdrop of stuffed toys.
Some contestants are fighting back by posting photos of themselves making crazy faces or piles of garbage using the same beauty hashtags. A mouse giving birth had 40 'likes' and was one of the most popular photos on the page.
Writer and social media consultant Hollee Actman Becker became concerned when her 10-year-old daughter inadvertently ended up in an Instagram pageant after someone posted her photo there.
"It hits you in the gut, like 'Oh my God, why is this happening and why is my child involved in this?'" she told ABC.
"I think it's so important to get in there and teach them the importance of supporting each other and celebrating who they are on the inside, not what they look like on the outside."
It states: "In the event that we learn that we have collected personal information from a child under age 13 without parental consent, we will delete that information as quickly as possible."
The company issued a statement saying that parents should monitor their kids online and that the online photo-sharing service takes precautionary measures against inappropriate behaviour.
"We are aware this is a trend taking place on virtually every media platform that teens engage with," it said.
"We work hard to make Instagram a safe, interesting and vibrant place for teens to spend time and express their creativity through photos.
"As with other social products, we encourage parents to take an active role in understanding what their kids are posting and who they are sharing with."
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