Web awareness should be promoted and users should be warned to fall in trap of these predators. Recently I have gone through some of the free chatting sites out of which very few have shown in their content the warnings for the users or you can say the parental guidance which can help them monitor the activities of their kids on the internet.
https://talkwithstranger.com is one of those sites which clearly warns users to be careful while providing your personal information to the strangers. For teen agers they have teen age chat room https://talkwithstranger.com/free-chat-rooms/teen-chat , where teen agers feel comfortable to share their experiences, knowledge and many ideas.