How Old Is Illinois?

High schoolers use fossils found in rocks to determine the age of the strata between Rock Island and Chicago. Pupils pretend they are geologists. They must determine the age of all rock layers between the Mississippi River and Lake Michigan. This is no small task, and here is a terrific lesson that provides you everything you need to lead your charges through the inquiry. Terrific photographs, worksheets, and resource links are embedded in the plan.