This short video (3:13 minutes) introduces complex adaptive systems and agent-based modeling concepts to middle-school students. It shows beautiful footage of birds flocking as an example of a complex adaptive system.
This short video (2:51 minutes) features two middle school girls describing and practicing pair programming. It is a great introduction to this method of learning programming and creating models.
This is an example of how a computer modeler uses various aspect of computational thinking while designing, creating and using a computer model as a tool to think with.