It’s no secret that our children are more adept at using technology than we are, but a new survey by computer security company McAfee suggests their using their skills to be sneaky. According to the survey, a shocking 70 percent of teens (up from 45 percent in 2010) may be hiding their online behavior from parents. After surveying 2,017 people, the company found that many teens accessed violent content (43%) or pornography (32%), and hid it from their parents.

But the survey also included some unexpected statistics. Fifteen percent of teens have hacked into social networks, 9 percent have broken into email accounts, 12 percent have met face-to-face with strangers they first came in contact with on the internet, and 16 percent say they’ve used phones to cheat on tests.

Given this, Robert Siciliano of McAfee urged parents to take an active role in monitoring their children, even if the internet confounds them.

“Parents, you must stay in-the-know,” Siciliano said. “Since your teens have grown up in an online world, they may be more online savvy than their parents, but you can’t give up. You must challenge yourselves to become familiar with the complexities of the teen online universe and stay educated on the various devices your teens are using to go online.”

As a way to keep tabs on kids, McAfee suggests installing parental controls. However, they say, parents should be upfront with kids if they decide to monitor their behavior. Otherwise, they run the risk of destroying trust.

[CNN]