It's an intriguing idea - unlike MySpace or Facebook, the "networks" are groups that require passwords to join, keeping the connections private and much more secure. The idea seems similar to Ning, a social networking site where anyone can set up their own "network" based on a shared interest or other connection. The difference here seems to be the extra level of privacy controls so kids, teachers, and/or parents can be careful who kids connect with online.
According to techcrunch's Mark Henderson,
"Kerpoof is working on making it possible for kids to collaborate over movies and stories, too, and on adding support for games and social puzzles later in the year. A type of virtual currency will be coming soon as well."Evidently the plan is to transition into a subscription-based fee service in the future, but for now it's totally free. People working with kids may want to get a good look at it now before they have to pay for it.
If you are just starting to check out social networking sites, the Library 2.0 Ning group may be something you want to look into - it's a group setup just for people interested in figuring out new services and features libraries can develop using recent technology and media trends.