Linux Distro for Kids?

Short, informal survey. Feel free to comment here or via private messages/email. I may not respond to all comments, but will read with appreciation any you make.

What is your favorite Linux distribution that is intended for use by kids, say anywhere between the ages of 8 and 18? If you have more than one, feel free to name each.

Why do you like it?

If your preference for kids is a standard distro and not one intended for that audience, which is it and why?