Assessing Conceptual Understanding of Geologic Time

Francis Jones
,
Earth and Ocean Sciences, University of British Columbia

This is one attempt to produce a validated concept inventory about geological time. Nineteen questions are multiple choice, one requires a point-form list of events to explain a geologic cross section. Key concepts addressed include the time scale, relative dating, absolute dating, and Earth history.

What learning is this evaluation activity designed to assess?

These questions should contribute towards reliable measures of understanding about the four key concepts listed above, because (a) geology research faculty helped define the key concepts, and (b) a cycle of expert and student validation interviews were used to refine the questions.

The test could serve as a test of prerequisite knowledge, as a pre-post test in courses emphasizing basic concepts of geologic time, or to compare fundamental knowledge of geologic time between differing groups or within groups longitudinally. There are no doubt other applications of concepts tests described in the concept test literature, or you may have unique situations where a concept test is useful. The test should not be used simply as a high stakes exam.

What is the nature of the teaching/learning situation for which your evaluation has been designed?

This is a concept test so questions are best used in class, not online or at home. Ideally it should not "count" much for grades. Results should be used to help refine the focus in a class, to ascertain where misconceptions lie, or to check on learning gains by testing both before and after a unit or course.

What advice would you give others using this evaluation?

Try to ensure students understand that this is not a "test"; it is a checkup on conceptual understanding. Offer participation marks or small components of a grade as incentive, but do not treat results as you would "exam" results.
These questions have been carefully validated in a large Canadian research university, using many interviews. Try to avoid adjusting them even a little bit. And, if possible, consider validating them again in your own setting with your own students.
Having said that, there is no harm in using portions of the test or modifying questions for your own setting, but if this is done, it will no longer be considered a "concept inventory" unless questions are validated with a student and expert interview cycle.

Are there particular things about this evaluation that you would like to discuss with the workshop participants? Particular aspects on which you would like feedback?

Do question sets like this really constitute a valuable contribution to ascertaining student understanding?
Do educators want such tests? i.e. what role can concept inventories play in teaching about geologic time?
Are others attempting to create such carefully developed assessments (other than Libarkin etal)?
Do the twenty questions in this concept inventory represent concepts that are universally considered important? What's missing? Which parts are not needed?