components of the course itself, such as the usefulness of the textbook or amount of material covered.
Interviewing students can provide rich, in-depth information about their responses to courses and instructors. When used appropriately, such interviews are usually either highly structured (following a specific set of questions and protocol), semistructured (with a few general items), or unstructured (e.g., “Tell me about this class”). Interviews can probe details and explore aspects of a course and the instructor’s role in it in ways that written questionnaires cannot. However, interviewing sufficient numbers of students to obtain an accurate picture of the instructor’s teaching and interpreting the results can require a great deal of time, rendering this approach somewhat impractical. Research also indicates that interviews are most helpful when they are used to provide feedback for improving teaching rather than for summative evaluation. Information garnered from interviews also can be more helpful to the instructor when the interviewing is done by an instructional improvement specialist, if available, or a trusted colleague (Centra, 1993).
An extremely useful and increasingly common approach to evaluating teaching effectiveness is to measure students’ knowledge or skills at the beginning of a course or unit of the course and again after some body of material has been covered in class. Instructors can then observe and quantify the amount of improvement and draw inferences about the instructor’s effectiveness in helping students learn the subject matter. For measures of student learning to be considered valid and reliable, however, considerable effort is required to develop pre- and post-learning tests that actually measure the kind of learning desired. In addition, changes observed in students’ learning and performance cannot be attributed solely to the effectiveness of an individual instructor. Many factors, including students’ ability and motivation to learn and even their health status when taking either examination, can also influence the outcomes.
Indirect measures of student learning can be obtained through questionnaires that ask students to assess their own achievement (e.g., “How much have you learned from this course?”). Some research (e.g., Pike, 1995) has shown that students’ answers to such questions are correlated with their performance on end-of-course tests.