The relative effectiveness with respect to knowledge and attitude of three instructional strategies for teaching the metric system to preservice elementary school teachers

Purpose The purpose of this study was twofold: 1. To compare three instructional strategies for teaching the metric system to preservice elementary teachers, and 2. To determine the relative effect, if any, of metric knowledge or gain in metric knowledge on attitude toward the metric system. The three instructional strategies compared were Lecture/Demonstration, Lecture/Laboratory, and Mediated. Procedures The sample for the study (N = 86) consisted of four intact mathematics classes (Foundations of Mathematics—a course specifically designed for prospective elementary teachers) at a junior college located near Houston, Texas. Three of the classes were taught identical content on the metric system with one of the instructional models Lecture/Demonstration, Lecture/Laboratory, or Mediated. The fourth class served as the control group and received no instruction in metrics. All instruction was conducted by the investigator over a one-week period (three class hours). For the Lecture/Demonstration group, the material was presented through lecture and illustrated with teacher-performed demonstrations using instructional aids such as a chalkboard, diagrams, metric measuring instruments, and objects to be measured. The Lecture/Laboratory strategy utilized a less active role by the teacher, but one which involved some lecture and sometimes a brief demonstration. Students spent most of the class time in activities involving the use of metric instruments for measuring length, mass, and volume. The class was divided into laboratory groups of three to four students. The Mediated strategy used in this study was an investigator-constructed slide/tape presentation along with accompanying worksheets. On three occasions tests were administered to the four groups to measure knowledge of the metric system and attitude toward metrics. A pretest was given during the week proceeding the period of instruction. A posttest was administered immediately following the treatments, and one month later a retention test was given. The McFee Metric Test (Forms I and II) were used to measure metric knowledge. Attitude was determined through use of the Purdue Master Attitude Scale to Measure Attitude Toward Any School Subject (Forms A and B). Analysis of Data The first general problem, comparison of the three instructional strategies, required twelve null hypotheses. Each of these hypotheses was treated with a one-way analysis of covariance. The second general problem, determining the effect of metric knowledge on attitude toward the metric system, was divided into two null hypotheses which were tested with stepwise multiple regression analysis. Major Findings 1. The Lecture/Demonstration, Lecture/Laboratory, and Mediated instructional strategies are equally effective (with respect to general metric knowledge and attitude toward metrics) for teaching the metric system to preservice elementary teachers for a one-week period. 2. With respect to teaching conversion among units within the metric system, all three methods are effective, but the Lecture/Demonstration and Mediated approaches are significantly more effective than the Lecture/Laboratory approach. 3. For preservice elementary school teachers, metric knowledge acquired during a one-week instructional period does not significantly affect attitude toward the metric system when initial attitude is moderately favorable.