Editorial: How Reliable is Teaching Evaluation? The Relationship of Class Size to Teaching Evaluation Scores

While teaching is an important component of engineering education, few widely adopted objective measures for evaluating teaching have emerged in our institutions of higher learning. The most frequently used measure nationally is the teaching questionnaire. This editorial does not attempt to analyse the much debated topic of whether teaching questionnaires are capable of measuring teaching effectiveness. What this paper does is quantify the relationship between class size and scores on teaching questionnaires. We report here, for the first time, that 1) compared to larger classes, course ratings are higher for classes of size 20 or less, and course ratings decrease when the class size increases within this small class group and 2) course ratings are independent of class size when the class size is larger than 20. This editorial is based on data from end-of-term teaching appraisals obtained from the archives at the Texas A&M University College of Engineering for all three semesters each year, beginning with Spring 1998 and continuing until Fall 2002