While the AntiScam apps are nice, you can use something like Web of Trust to highlight questionable links and such on more than just Facebook. But the monitoring apps are very useful and can help consolidate your children's online activities into one place… Definitely worth a look.

Lock down your social media with essential security add-ons | PCWorld
Are you doing everything you can to protect your kids and yourself on social networks? These apps and services can keep an eye on their and your accounts and alert you to any dangerous activity.