This is an activity designed to help the instructor to introduce the concept of geologic time. This is useful in many entry level geology classes, as well as in upper division classes as a "pre-class assessment" tool.
It is as comprehensive as the instructor wants it to be. Essentially the assignment is a blank geological timescale. The original activity description, hosted on the very reputable Science Education Research Center (SERC), and accessible on LOUIS, gives the instructor a few idea on how to actively engage students actively working together on the material from the start of the course. However, essentially the assignment is a blank slate: a simple geological time scale and the instructor can easily modify the assignment by choosing a different prompt.