Mastery Assessment

This web page is by Maria Waller, based on a document produced by participants at the 2012 workshop on Teaching About Time.


A mastery assessment aims to determine what students have understood from the material covered during a term and, further, how well they can apply that knowledge to broader problems. A narrowly-focused mastery assessment might address whether students have met an individual learning objective for a course. This could be accomplished in many ways, one example being questions administered via quiz or assignment during a term, where each question targets a particular learning goal. A more comprehensive and challenging mastery assessment could be a capstone project that requires students to make observations, collect and organize data, and integrate those observations and data into a geological interpretation by applying what they have learned during the course.

Included below are examples of possible mastery assessment questions for an introductory course in geology or historical geology. They are not intended to be a definitive or comprehensive set of assessment questions to measure your students' mastery of concepts related to geologic rates and time. Rather, they are intended to serve as examples, which you might modify or use as models to design your own mastery assessment questions.

The examples given here progress from assessing relatively simple cognitive tasks (knowledge and understanding) to more cognitively demanding tasks (application, analysis, and synthesis). The more cognitively challenging assessments inherently incorporate a learning component in addition to measuring students' learning.

Example Assessment Questions

Dates in Earth history

Assessment targets: Students will demonstrate

  • Knowledge of notable dates in Earth history
  • Basic understanding of numbers and proportions

The following list includes some significant dates in the history of the Earth: 3,465,000,000 years ago, 66,000,000 years ago, 4,600,000,000 years ago, 11,700 years ago, 6,000 years ago, and 4,000,000,000 years ago.

  1. Put these dates in chronological order from oldest to youngest.
  2. Choose 3 dates from the list above. Use a piece of graph paper, and plot these dates to scale on a timeline. Show your calculations.
  3. Each of the dates above corresponds to one of the geologic events listed below. Match the events with the dates.
    • Oldest rocks on Earth
    • End of Mesozoic Era (mass extinction, including dinosaurs)
    • Beginning of recorded history
    • Origin of Earth
    • End of Pleistocene Ice Age
    • Oldest known fossils of organisms

Reconstructing Earth history

Assessement targets: Students will demonstrate

  • Understanding of and ability to apply the principles of original horizontality, superposition and cross-cutting relationships in order to sequence a set of rock units.
  • Understanding of how geoscientists use radioactive decay of certain isotopes to determine numerical dates.
  • Understanding of how geoscientists combine radiometrically-derived dates with relative ages to date a geologic feature or event.

Consider the cross-section shown to the right.

  1. Interpret the relative ages of rock units A-E and fill in the corresponding blanks below. ____ = Youngest




    ____ = Oldest
  2. Discuss the evidence and reasoning that you used to put these rock units in order by age.
  3. Consider where Rock Unit F fits into your chronological sequence above. What is the uncertainty involved with this? Explain.
  4. How could radiometric dating help you to eliminate the uncertainty in question 3? What additional information would you need? What other method(s) for dating rock units could help you to determine that information?
  5. Why can absolute (numerical) ages be determined for some but not all rocks? In your answer be sure to include an explanation of how the process of radioactive decay is integral to radiometric dating.

Capstone Projects

Assessment targets: Students will demonstrate

  • the ability to conceptualize scaled examples of geologic time
  • the ability to place events in sequence, using information about both relative and absolute time
  • the ability to use evidence to support interpretations
  • the understanding that geologic processes occur at different rates over different time spans

To address the above learning objectives, you could design a capstone-type project that students will work on over several weeks. This project could require students to

  • Make observations of geologic materials
  • Develop interpretations based on their observations
  • Compile their observations & interpretations into a coherent story describing the geologic history for the area
  • Explicitly provide evidence for their interpretations

See, for example, these activities: