Qimo

Qimo is a lightweight Linux distribution designed for use by children. Qimo is based on Ubuntu. Qimo 2.0 uses Ubuntu 10.04 LTS as its foundation. XCFE is the interface used by Qimo because it is fast and lightweight. A dock at the bottom of the screen contains icons to all of the educational software for easy accessibility. The distro is built and maintained by a couple from Florida in the USA.

Link to Qimo website -> http://www.qimo4kids.com

Pros

based on a nice stable version of Ubuntu
low hardware reqs (256MB RAM, 6GB HD)
easy to use interface
fast interface
includes educational software
locale can be changed to other languages
can be run off a liveCD if needed
entire Qimo install image fits on one CD media

Cons

there are a lot of updates after initial installation
not all software is locale based so there may be some English mixed in
non-Ubuntu updates may be sporadic
installing on some systems can generate an error requiring installation via liveCD session
icon dock at bottom (or "task bar") obscures some install-time response options
may be too simple for older students or those who have experience with Edubuntu