Early PER Findings

Early results from Physics Education Research, relevant to physics instruction
Jose Mestre

This document is quite old (early 1990s) and mentions nothing about all the relevant research since then. It's also lacking references. Caveat emptor.

The areas of cognitive research we will focus on are: (1) the prevalence and virulence of misconceptions; (2) the differences between the ways that experts and novices store domain-specific knowledge and solve problems; (3) the importance of goal-free activities; and (4) the effects of "meta-communicating" with students about the learning process. Each area has critically affected the development of our approach, and therefore, each area is reviewed to help you understand the construction of our materials and how they should be implemented.


An important area of cognitive research is the study of misconceptions. Results show that misconceptions: (1) are extremely common; (2) are not easily displaced; (3) can be found (even) among experts; and (4) hinder understanding. It appears that people continually and unconsciously build models of how the world operates. The human brain seeks patterns and quickly establishes categories. Patterns of experience are put into models, but often, these models are based on insufficient experience. Furthermore, these models, misconceptions included, affect how later experiences are interpreted.

Thus, demonstrations that teachers show to students often can reinforce misconceptions rather than dislodge them. Later, especially if their models have been (reasonably) successful at getting the right answer, students are extremely reluctant to abandon them. When educators are not aware of the models that students are using to interpret experiences, answer questions, and solve problems, it can be a shock and a mystery when previously successful students get wrong answers. In fact, misconceptions may have been there all along, but they were not manifested by the interaction and communication between the student and teacher.

Expert-novice differences

The following table summarizes some of the differences between experts and novices that cognitive research has studied and revealed. We believe that one of the tasks of good curriculum materials is to encourage beginners to think more like experienced problem-solvers.

Experts Novices
Knowledge Characteristics Large store of domain-specific knowledge Sparse knowledge set

Knowledge richly interconnected and hierarchically structured Disconnected and amorphous structure

Integrated multiple representations Poorly formed and unrelated representations
Problem-Solving Behavior Conceptual knowledge impacts problem-solving Problem-solving largely independent of concepts

Performs qualitative analysis Manipulates equations

Uses forward-looking concept-based strategies Uses backward-looking means-ends techniques
Table 1: A summary of expert-novice differences

Goal-free vs. goal-directed questions

The prevailing approach to teaching physics has been to lecture, assign homework problems, and give exams. Although teachers usually emphasize the importance of concepts, students generally do not understand concepts, nor do they use them to solve problems. One reason might be cognitive overload, in which students are so focused on the answers, and are paying so much attention to the questions asked, that they can not also focus on problem-solving skills and do not notice the patterns intended by the teacher; they never see the connections and the repetitions among the assigned problems.

Homework and exam questions in the prevailing approach are goal-directed, and it is believed that asking open-ended, goal-free questions reduces cognitive overload. This allows students to devote greater cognitive resources to other activities, such as reflection, and leads to improved understanding of subject matter. It is recommended, therefore, that fewer goal-directed questions (but not none) should be given to students, and that more conceptual questions should be asked.

Effects of meta-communication on learning

Meta-communication is defined to be the process of communicating information and knowledge other than content. It usually involves higher level skills, such as: different ways to organize the material; how people think; how people solve problems; what to study in a textbook; how to read and extract information from textual material, etc. Meta-communication is intended to help students learn how to learn, by helping them learn how they learn best and by pointing out the relevant issues along the way.

In a recent study, we have shown that students in a traditional college engineering physics sequence can learn how to write qualitative strategies before they solve problems. Although students struggled with the task, by the end of one semester, many were able to write "expert-like" strategies that correctly identified: (1) the principle they would use to solve a particular problem; (2) the justification and applicability of the principle to the problem; and (3) the way in which the principle would be applied to the problem.

Our own experience confirms that people must be actively engaged in the structuring of knowledge for it to be useful for solving problems and understanding content. Meta-communication is the way in which teachers encourage (sometimes reluctant) students to consciously construct their own self-consistent models of how the world operates.


We believe that educational materials designed with reference to these research results will likely be more effective than materials designed otherwise. To help organize these findings, and to represent them in a useful way, we have developed a model for the acquisition, storage, and utilization of knowledge. Our model is consistent not only with research findings but also with our own reflections on the problem-solving process.