I think of sites like Club Penguin and ZooKazoo as social networks on training wheels.

These sites, generally aimed at kids between about six and 12 (Penguin goes up to 14 but it's hard to imagine they have very many users that age), provide an opportunity for kids to interact in a much more limited way than social networking sites like MySpace, Facebook and Bebo which are off-limits to pre-teens.

In both Club Penguin and ZooKazoo kids represent themselves as "avatars." An avatar is a cartoon-like character that serves as the surrogate for the child. The image of the avatar (not a picture of the actual child) walks around, "talks" with other characters and engages in various games and experiences. In the case of Club Penguin the avatar is a particular penguin that the child chooses. In ZooKazoo your avatar is called a "zelf" and it can be a monkey, cat, bear or other character.

Children can communicate in these virtual worlds but there are limits. Either they can have free chat or—at the parent's option—be limited to chatting only by selecting pre-existing phrases. Both sites have filters to prevent "bad words" as well as dumb stuff like when a child tries to type in a phone number.

Even with safety tools in place, parents still need to monitor how their kids are using these services. Exercising good cyber-citizenship (don't be mean or bully) is very important and it's also important for kids to know that if anyone is mean to them, it's not the victim's fault that someone is being rude and obnoxious.

Both sites have limited free memberships but to get full benefits families have to pay—typically about $5.95 a month. The sites do not display advertising.