This Powerpoint walks students through the process of developing geological theories by studying and analyzing the same evidence that was considered when the theory of plate tectonics was developed. This documents requires no prep at all -- and will cover 3-5 days of science class.
The intention for this document is that students work in teams as geologists to study the evidence, answer questions, and develop their own theories. Questions for assessment and reflection are included. I like to use these questions in blog form, but you could also have students write their answers in a journal or even use them to guide classroom discussion.