ConcepTest CAT 

Arthur B. Ellis, Clark R. Landis, Kathleen Meeker
Department of Chemistry
University of Wisconsin-Madison

WHY USE CONCEPTESTS?
•	The instructor obtains immediate feedback on the level of class understanding.
•	Students obtain immediate practice in using SMET terminology and concepts.
•	Students have an opportunity to enhance teamwork and communication skills.
•	Many instructors have reported substantial improvements in class attendance and attitude toward the course.

WHAT ARE CONCEPTESTS?
The instructor presents one or more questions during class involving key concepts, along with several possible answers.  Students in the class indicate by, for example, a show of hands, which answer they think is correct.  If most of the class has not identified the correct answer, students are given a short time in lecture to try to persuade their neighbor(s) that their answer is correct.  The question is asked a second time by the instructor to gauge class mastery.  Many variations on this general CAT exist.  A video clip illustrating the method is part of this CAT.

WHAT IS INVOLVED?
Purpose of Assessment: To estimate class learning in real time.
Instructor Preparation Time: Some time is needed to create ConcepTests.  For some disciplines, hundreds of sample questions exist on websites as a time-saving resource.
Preparing Your Students: Students require minimal training though sustained use in class helps students become comfortable with the method.
Class Time: ConcepTests typically last from less than a minute to several minutes.
Disciplines: Appropriate for all.
Class Size: Best with classes of at least a dozen students.  Successfully used in large lecture classes.
Special Classroom/Technical Requirements: None.  The method can be used in conjunction with worksheets, lecture demonstrations, and computer animations and filmclips.
Individual or Group Involvement: Small group of 2 or 3 students.
Analyzing Results: Minimal.
Other Things to Consider: It is more difficult to predict how much material will be covered in a lecture.  It may take a sustained effort for an instructor and class to become comfortable and work effectively with ConcepTests.

Contents
•	Description
•	Assessment Purposes
•	Limitations
•	Learning Goals
•	Instructor Goals
•	Suggestions for Use
•	Examples
•	Variations
•	Analysis
•	Pros and Cons
•	Theory and Research
•	Links
•	Sources
•	Arthur B. Ellis, Clark R. Landis, Kathleen Meeker

Description
Many instructors have become far more satisfied with their SMET course simply by taking a few minutes during a typical lecture and posing a conceptual question called a ConcepTest to their students. Eric Mazur, a Harvard physics professor, developed this method for teaching undergraduate physics courses.<sup>1</sup>  These questions inform or calibrate students as to how well they understand what the instructor has identified as key ideas; and they calibrate instructors as to class mastery of these ideas at the time of their presentation.  ConcepTests thus make the lecture a vehicle for bringing student and instructor expectations into alignment. ConcepTests are distinguished by a classwide vote-discuss-vote cycle built around a question that captures a key concept identified by the instructor.  The format of a ConcepTest is shown schematically below, and illustrated in a quick-time video clip on the website (http://www.wcer.wisc.edu/nise/cl1). 

The ConcepTest process.  

An example of a ConcepTest that could be used in a variety of SMET courses is the following:

If a blue solution cuts the amount of red laser light reaching a solar cell, which counts photons as photocurrent, in half…

What happens when a second identical solution is added?

Ask your class to vote:  "How many of you think that a quarter of the laser light will now reach the solar cell?" (Pause to observe response by, e.g., show of hands.)  "How many of you think none of the light will now get to the solar cell?" (Wait as before.)

If most of the class has correctly noted that one-quarter of the light will be transmitted, you can quickly affirm why this is correct and continue with the lesson.  If the majority of the class does not select the correct answer,  you ask your students to convince their neighbor(s) that their answer is correct. An option you might use is to give a hint, e.g., a reminder that each cuvette will transmit half of the light that enters it.  After a short discussion period you have the class vote a second time. If the class has now selected the correct answer, a quick explanation is again appropriate; if the majority of the class has not reached the correct answer, a more detailed explanation can be presented.  Sometimes the most effective ConcepTests are those for which the class has converged on an incorrect answer, as these questions identify a shared misunderstanding. Occasionally the class may even be thunderstruck by the correct answer, which, in this case, could be revealed by doing the experiment as a demonstration.

In general, ConcepTests can be used to strip a concept to a particularly simple case for analysis, to extend a concept in a new direction, to couple concepts, and to confront misconceptions, which can be folded into the possible answers to a ConcepTest.  ConcepTests are often constructed to occupy the class for short periods of time, ranging typically from less than half a minute to several minutes. Judging when best to interrupt the discussion is an important and acquired skill.  In most classes the noise volume will slowly build as students come to task, and then the volume will drop.  The students' attention should be regained before the volume increases again; when this occurs, students have often moved on to other subjects.

With this non-graded, non-threatening format there is an opportunity for all students to discuss a concept with their classmates and to inform the instructor of the extent to which the concept is understood by the entire class.  Because everyone is encouraged to participate, students are less fearful that their possibly incorrect answer will be publicly exposed to the entire class and thus are more likely to join in the discussion.  

Assessment purposes
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