What were they THINKING when they posted that?
They probably weren't thinking at all, according to a team of researchers from Pennsylvania State University in the US who say teens and adults differ when it comes to managing privacy risk online.
"While most adults think first and then ask questions, teens tend to take the risk and then seek help," says Haiyan Jia, a post-doctoral scholar in information sciences and technology at Penn State.
It's hard for adults to understand, says Jia, because they've already learned their lesson and have become used to weighing the possible consequences of their actions.
When it comes to privacy concerns and the information they disclose, teens exhibit a paradoxical disconnect, says Jia.
Teens look for protection rather than prevention when it comes to risk, says Jia, including turning to adults, removing the questionable post or closing social media accounts.
Self-expression through social media, and using the platforms as an outlet to gain acceptance from their peers can lead to too much disclosure, according to the study.
Consequences of revealing vital contact information and exchanging photos with strangers can be grave, and parents' initial response to such behavior is to forbid internet access.
Yet completely avoiding risks could cause other problems, says Jia, who presented her study on Tuesday at the Computer-Supported Cooperative work and Social Computing conference.
"First, I can't imagine a teen growing up and avoiding the internet and online communications in this age," says Jia. "But there's also a danger that without taking on the minimum risks, teens will not have access to all the positive benefits the internet can provide, nor will they learn how to manage risk and how to safely navigate this online world."
She advises parents to visualize swimming lessons as a comparative experience to learning to use the Internet.
"You make sure they enter the water slowly and make sure they know how to swim before you let them swim on their own and in the deeper parts."
Jia and her colleagues used data from the Pew Research Center's 2012 Teens and Privacy Management Survey, which worked with 588 US teenagers to assess social media behaviors.