There's no doubt in my mind that the previously mentioned robotics initiative Project Butiá is one of the coolest community projects which has developed around Uruguay's Plan Ceibal. Particularly the combination of a solid hardware platform with great software support in popular activities such as Turtle Art make Butiá a very versatile and powerful platform.
Now more recently Butiá's Andres Aguirre sent out a link to a report about a recent event for schools which the Faculty of Engineering in Montevideo had organized:
The last 16 and 17 of September was the robotic event called sumo.uy organized by the public Uruguayan faculty of engineering. In this event there were two challenges for the butiá robot, were schools from Uruguay come to participate with the robots we gave them last year, showing the great work that they were doing. One of this challenges was the "basic butia" (PDF) wich consist in the implementation of a line follower robot wich must be able to evade obstacles.
It sounds like the event was a great success and looking at the video below you can also see that the pupils did a nice job in programming the robots.
Head over to this report on Butiá's Web site for more photos and videos of the event.