This colorful, 3-D model correlates rock layers to geologic time periods. Constructed of durable vinyl, the 23 1/2" W x 24 1/2" H model features 21 replica fossils which students match to appropriate strata. Model illustrates the aquatic and terrestrial life living in the Pre-Cambrian era through the Cenozoic. In addition to eras, periods and years are also indicated on the chart. Includes a detailed Teacherís Guide with classroom activities.