Think-Pair-Share: Analyzing changes in supply & demand and predicting impacts on equilibrium

This page authored by KimMarie McGoldrick, University of Richmond
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This material is replicated on a number of sites as part of the SERC Pedagogic Service Project


In a think-pair-share activity, students first work independently to demonstrate graphically how events change supply and/or demand in specific markets and explicitly describe the adjustment process from the original to a new equilibrium. Students are then paired to share and revise their answers before being randomly chosen to report answers to the larger class.

  • This exercise is designed for a principles of microeconomics course; however, instructors reviewing supply and demand concepts in any course might find them equally useful.
  • Follow up exercises are provided so that instructors might engage students with additional problem solving outside of class or develop additional cooperative learning exercises on these and related supply and demand concepts.

Learning Goals

Identify factors which shift supply and demand (Proficiency: accessing existing knowledge).

Translate context specific events into such factors.

Analyze market outcomes such as changes in equilibrium price and quantity (Proficiency: displaying command of knowledge).

Follow up exercises are provided which cover other key components of the supply and demand chapter including mathematical solving for equilibrium and the calculation of consumer and producer surplus.

Context for Use

Knowledge required: This exercise is intended to be administered after a standard chapter on the market (covering supply, demand and equilibrium) is covered by the instructor.

Class size: This exercise was originally designed for a class of 25-30 students, but it can be easily adapted for smaller or larger classes.

Time required: The exercise is designed to take a total of 20 minutes.

Description and Teaching Materials

Two handouts are provided to support this exercise. The Student Handout for Supply and Demand Exercise (Microsoft Word 2007 (.docx) 19kB Jun4 12) includes instructions for the think-pair-share exercise. Answer Key for Supply and Demand Exercise (Acrobat (PDF) 63kB Jun4 12) is a detailed answer key for the exercise.

  • These additional exercises can also be incorporated into a more sophisticated cooperative learning process, the send-a-problem.

Teaching Notes and Tips

Class size poses no constraints on utilizing this exercise as it only requires that instructors facilitate the pairing of students after the initial independent work is completed.

The 20-minute exercise is comprised of the following think-pair-share components: 8-10 minutes for students to work independently to solve the problem, 5-7 minutes to share and revise answers, and 5 minutes for reporting back to the larger class.

As part of the set-up for this exercise, students are told to treat it as if it were an exam question in order to test their comprehension. Students are encouraged to attempt the exercise during the think stage of the exercise without looking at their notes and to provide a carefully constructed (and labeled) answer. Requiring students to independently formulate a draft answer in this stage ensures individual accountability.

Student pairs are the mechanism by which positive interdependence is facilitated. In this exercise, since two students are working together towards a single answer, it supports positive interdependence through output goal interdependence.

During the sharing, stage of the exercise students methodically take turns presenting their answers to different parts of the exercise (see instructions on exercise handout) as their partner reflects and asks questions of clarification through face-to-face (promotive) interaction. This also supports positive interdependence by explicitly generating role interdependence.

During the thinking and sharing stages of the exercise, it is imperative that the instructor move throughout the classroom to check in with students, monitoring progress, and intervening when necessary. Although instructors may be tempted to directly answer student questions during this period of time, student learning is enhanced to a greater degree if the instructor guides struggling students by posing reflective questions back to them.

Conclusion to exercise:

Reporting back to the larger group can be facilitated by tossing a soft ball to a random pair and asking them to share part of their answer. Depending on time constraints, students can be asked to orally describe shifts in supply and/or demand and the resultant outcomes, or they may be asked to come to the board and replicate their graph as well. Thereafter, students toss the ball to another pair to share a remaining part of the exercise. This process continues until all parts of the answer have been covered.

Alerting students in advance that some pairs will be randomly called upon to explain their answers to the class at the close of the exercise helps to motivate students to work diligently on the task during class and - because the reporting out process occurs in this manner (via a somewhat random draw of students) - students are more engaged in the reporting out process.

Further considerations:
The main exercise is applicable to all institution types and levels. Follow up exercises are similarly applicable with, perhaps, the exception of one problem which requires a mathematical solution for equilibrium.


Since students are receiving feedback regarding their understanding during the sharing stages (in pairs and across the larger group), they are participating in formative assessment.

This particular think-pair-share exercise has no formal summative assessment directly tied to it. However, it is set up in a manner that mimics question content and structure which appears on quizzes and exams covering this material. Exercise answer keys are provided to students directly after the exercise (either through handouts or electronic facilitation) to reinforce the learning process.

References and Resources