"Soon, everyone will have an iPad or tablet and that is like having Facebook and other sites in your pocket," Crouchley said.
"Social media are not going away so parents need to get involved so they can keep their children safe."
High-profile cases such as that of Canadian teenager Amanda Todd, who was harassed relentlessly online until she killed herself, have sparked calls for more controls.
Current statistics show 2,267,300 New Zealanders already use Facebook, but youths are increasingly signing up to sites such as Twitter and YouTube, neither of which have age restrictions.
Crouchley said it had become common for people to bully others through Twitter to get more followers. Others set up anonymous Facebook pages to reveal secrets or make up stories about others.
There were plenty of settings and restrictions parents could use to limit the time their children were online and restrict who had access to their accounts.
There needed to be arrangements where parents were "friended" by their children but agreed not to post embarrassing photos or comments, he said, which could drive their children away.
Parents did not need to be social media-savvy to understand the workshops.
Information can be found at www.socialmediaseminars.co.nz