Abstract

There is much literature on the theory, the practice and the research on critical thinking skills. Several theoretical definitions have been proposed for these skills which are also referred to as "higher order thinking skills". Although Bloom's taxonomy of cognitive skills still serves as the groundwork for the study of critical thinking skills, categories such as "analysis", "synthesis" and "evaluation" have been refined over the years by subsequent scholars and researchers. Hence, more current models tend to include aspects such as metacognitive skills, handling multiple perspectives, decision making skills and critical thinking dispositions. The rationale for teaching critical thinking skills at all levels of the educational process is not questioned: it is generally assumed that these skills are desirable for any students to function adequately in society. The challenge, however, becomes one of teaching methods. It is assumed that constructivist approaches provide more opportunities to engage critical thinking skills than regular teacher-centered methods because they usually offer novel problems or perplexing situations. However, research on teaching critical thinking skills, especially in higher education, remains sparse. Most studies, exploratory in nature, are conducted with very small groups of participants, mainly in social science domains. Content of online collaborative discussions, usually facilitated by an instructor who uses a scaffolding strategy, tends to be the preferred source of data for research on critical thinking skills. This study investigated the effect of task design on the development of critical thinking skills by engineering students. It was hypothesized that the introduction of complexity in instructional activities would increase the incidence of critical thinking skills. Specifically, a "complexity" variable was incorporated in the instructional tasks carried out individually by the participants. Participants (N = 65) were fourth year engineering students registered in the course "Impacts of Technology on Society" (Engr 492) at Concordia University. A quasi-experimental time-series design was used to carry out this study, which was conducted over a period of six weeks. Five instructional tasks constituted the treatments; students' written productions provided the main source of data. Individual feedback and instructor's interventions during the data collection were controlled. Students were debriefed upon completion of Task 4. Performance on the first two tasks provided the baseline for the pre-treatment level of students' critical thinking skills. The baseline of the treatment group was compared with that of the non-treatment group to establish group equivalence. A modified version of Herrington and Oliver's synthesis of critical thinking skills instrument was used to analyze the data. A trend analysis confirmed that the overall treatment had a positive effect on the incidence of observed critical thinking skills. Results indicated that the first level of the complexity variable embedded in the case study (Task 3) triggered a higher incidence of critical thinking, as well as a different set of critical thinking skills. On the second level of complexity, students in Tasks 4 and 5 showed fewer instances of critical thinking skills than in the earlier Tasks. An exploration of the outcome on those tasks suggests that simulation, as an instructional approach, provides too much complexity for individual learners, and so does not trigger a higher incidence of observable critical thinking skills. The results are discussed both in terms of implications for instructional design and for conducting research about critical thinking.