Going through adolescence has never been easy, and in recent years, the internet has exposed tweens and teens to myriad new ways to fuel their insecurities. The latest trend: A growing number of youngsters, mostly girls, are posting YouTube videos asking commenters, "Am I ugly?" What's behind these "disturbing" videos? (See a sample clip below.) Here, a brief guide:

How common is this?
On YouTube, says Amy Graff at the San Francisco Chronicle, "if you type 'Am I ugly?' or 'Am I pretty'" into the search box, "dozens of videos pop up, including one of an 11-year-old girl who poses for the camera, twirling her shoulders, smiling big, and pulling her long hair out of a pony tail." Then she asks, "Do you guys think I'm pretty?" One such video, uploaded in December 2010 by a girl who says people tell her she's ugly, has been viewed 3.4 million times.

What do commenters say?
Some people are kind, posting words of encouragement, such as, "you're super pretty" or "you're not ugly, society is." But others "fall into extremes," says Daisy Dumas at Britain's Daily Mail, "either over-the-top compliments, suggesting sex, or reflecting a level of animosity that is stunningly harsh." One commenter told a young girl, "your forehead scares me," while other comments are even more cruel, or racist.

Who's to blame?
Many people are worried about the girls, and angry at YouTube commenters. "A 12-year-old isn't mature enough to deal with vicious remarks made by their mean-spirited peers and sick-minded internet trolls," says Graff at the San Francisco Chronicle. The "cavalier meanness" of some of the remarks are "heartbreaking." "Leave it to anonymous internet commenters to make middle-schoolers feel worse about themselves than they already do," says Katie J.M. Baker at Jezebel. "How do we get YouTube to make this illegal?" Don't pin this on YouTube, says the Houston Chronicle's MomHouston blog. This is the result of a widespread "parenting fail."

Sources: Daily Mail, Houston Chronicle, Jezebel, SF Chronicle

Watch one of the controversial videos for yourself: