Teaching geologic time and rates of landscape evolution with dice
Kate Ruhl, Massachusetts Institute of Technology
Landscape evolution provides a convenient framework for understanding geologic time and rates because students can observe how processes like erosion and deposition shape their surroundings. In this example, students build 3-D sandbox models based on topographic maps and design and stage a "virtual adventure race." Sandbox landscapes are used to illustrate erosional processes,while local examples are used to discuss landscapes as transient or steady over different time- and length scales. Dice experiments illustrate radioactive decay and the shape of the age equation curve, and 14C dating, geochronology and thermochronology are introduced as "stopwatches" that start when a plant dies, a crystal forms, or a rock nears the surface and cools to a certain temperature. The sandbox model and thermochronometer "stopwatches" are combined to measure erosion rates and rates of landscape change. Ultimately, model rates (cm/hour) calculated from stopwatch times on the order of seconds can be related to geologic rates (km/My) calculated from real million-year-old samples.

Rates of Change and Deep Time in the Middle Grades Classroom
Fred Siewers, Western Kentucky University
The nature and scientific measurement of geological and cosmological time are among the most misunderstood and difficult to teach concepts in all of K-12 science education. To address this issue, a multi-disciplinary team of geologists, astronomers and education professionals at Western Kentucky University developed a series of professional development workshops for pre- and in-service middle grades teachers. The participants clearly advanced their content understanding of geological and cosmological time and the implementation plans received clearly show a desire to apply many of the activities learned in the workshop.