Don't you think the XO can be used to help connect a western school student, to a lower year student in another country to act as volunteer tutor and mentor?
One way to go about this is to create a web conferencing website, where xo users can come to obtain bored students to receive some help.
Studies has shown that students learn more if they teach another person about the same topic. This is obvious as the tutor has to know his/her stuff, if the tutor/mentor is to teach well.
It also helps ensure that students from developing countries, are getting the fullest education they need.
http://wiki.laptop.org/go/Remote_tutoring
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Btw... it doesn't have to be restricted to western student tutoring students in other places. The students from the same country or even the same school can be made to tutor each other.
Perhaps this would be even more effective, if you can create a point like system. Where at a certain period of each day, the classroom is expected to be ready to help another student out from another classroom. If the student found the virtual tutor to be useful, then the student can give that tutor a point. This point can then be spent on virtual items, or customizing their personal OLPC webpage.