The study found large differences between what parents know about their teens' social networking use on sites, such as Twitter, Facebook and Tumblr, and the level of monitoring their children knew of.
It found 70 per cent of parents checked their teens' text messages on their phones but 70 per cent of teens were unaware of it, and while about 84 per cent of parents said they monitored online useage, just 39 per cent of teens were aware they were being spied on.
Just 14 per cent of teens thought their parents were well informed about what they were doing on Twitter and while 95 per cent of teens reported feeling safe online, 94 per cent of parents disagreed with them.
Parents saw stranger danger as their top worry.
The US study, which did not make global comparisons, comes as 55 schools in the Auckland and Northland region were found to be linked to school-themed Facebook pages run by students, with 26 linked by the student users to graphic sexual material, profanity, alcohol or drug-use at school or tormenting of other students.
In the US, the number of young people suffering cyber-bullying ranged from 15 per cent to 60 per cent, although the rate remained lower than the prevalence of physical or "offline" bullying, Mr Balkam said.
That compared with one in five New Zealand high school students who reported being cyber-bullied in a 2007 survey.
For Kiwi parents whose kids were being targeted, he said the best step was reporting the bullying - both to website administrators and the school.
And for mums and dads unsure of how to address their concerns around the internet, Mr Balkam encouraged working with their kids as early as possible - and not against them.
"If you come at your kids with fear, they are just going to switch off and think you don't know what you're talking about," he said.
"It's important for parents not to overreact, to try to calm down a little bit, and not let fear get in the way of reasoning. This after all is their future - we are never going to go back to the 1950s ... so parents have to find that balance."
Cyber-bullying is one of many issues this week's conference, drawing more than 100 delegates and themed Our Community: Our Challenge, seeks to address.
NetSafe chief executive Martin Cocker said the overall aim was to find better solutions, including strengthening controls individuals have over their personal information and giving scam victims a greater chance of recovering lost money.
"We as a community need to work together to develop solutions."
NetSafe conference
"Our Community: Our Challenge"
* Where and when: Ilott Theatre, Wellington Town Hall, today and tomorrow.
* Who's going: Communications and Information Technology Minister Amy Adams, Justice Minister Judith Collins, Privacy Commissioner Marie Shroff, chief Human Rights Commissioner David Rutherford, international experts Stephen Balkam (US) and Michael Carr-Gregg (Australia) and representatives from Facebook, Google, Microsoft, Sophos, the NZ Game Developers Association, the Ministry of Education, the National Cyber Security Centre, New Zealand Police and the Department of Internal Affairs.
* Key addresses: Amy Adams (10am today), Judith Collins (9.30am tomorrow), workshop "I Have Rights" (2pm today), Stephen Balkam (9.40am tomorrow).
* Website: www.netsafe.org.nz/conference2012.
