Rather than straight up person-to-person video calls like Apple’s Face Time, Facebook Messenger or the recently introduced Whats App feature, Kik has added a less intrusive video chat option for its 300 million-plus registered users, with support for groups of up to six.
You could start with an opening comment like "I've heard about kids going into video chat rooms to interact with people they don't know. If they're oblivious to it, said Dess, "you can just drop the subject." For the time being at least.
Back in the 1990s there was a service called CUCME (as in "see you see me") that let you strike up a video chat with strangers.
I remember trying it when I got my first PC video camera and encountering a topless female on one of my first forays.
On a Windows machine, you can open up the device manager, click on Imaging devices, right click on the line for your integrated camera and select disable--do not select uninstall unless you want to completely remove the software that operates the camera.
If you have a parental control filtering program you can also block but, for most families, your first line of defense should be to talk with your kids.The site has a disclaimer saying it's for users older than 16, but unlike most sites with age restrictions, it doesn't ask users to enter a date of birth.