The Effects of Direct and Problem-based Learning Instruction in an Undergraduate Introductory Engineering Graphics Course.

Abstract

In this study, the researcher examined the effects of problem-based learning and compared any statistical gain in knowledge, skill, and attitude to traditional teaching of engineering graphics. Problem-based learning was hypothesized to have a positive effect on knowledge, skills, and attitude of students in a traditional engineering graphics course.

The study sample was forty-eight (N = 48) students in a Foundation of Graphics course at North Carolina State University. The quasi-experimental study involved a pre-test / post-test control group, using a single control and single treatment group consisting of 24 persons per group.

The independent variable was pedagogical strategy, and the dependent variables of knowledge pre-test and knowledge post-test measured graphic content knowledge, allowing for direct gain comparisons of engineering graphics to the control and treatment groups. Other dependent variables comprised a CAD skill evaluation that measured students' skill in creating a three-dimensional CAD model and an attitude survey (MSLQ) to compare attitude associated with traditional versus problem-based learning. The pedagogical PBL treatment was a series of 20 in-class exercises, where students worked in small groups to complete small-problem scenarios, including reverse engineering of parts.

To determine whether groups differed on more than one dependent variable, an ANOVA was used to analyze data and investigate difference and gain between traditional-instruction and problem-based learning for knowledge, skills, and attitude. Each ANOVA investigated if any significant difference or gain (p < 0.5) existed between groups and was used to determine gain between dependent variables.

The means on the pre- and post-tests measured if the two groups were significantly different in their prior knowledge and skill. The comparison of means and ANOVA of the MSLQ survey score revealed no significant differences in attitude. The result of hypothesis #1 (knowledge), F(19, 23) = 2.12, p = 0.24, indicated no significant gain. The result of hypothesis #2 (skill), F(1, 23) = 0.03, p = 0.85, indicated no significant difference, and the result of hypothesis #3 (attitude), F(21, 527) = 1.57, p = 0.50, indicated no significant difference. Further studies were recommended using similar or other variables to determine if more benefits can be attributed to problem-based learning when teaching engineering graphics.