@Article{GobertClement1999,
author = {Gobert, Janet D. and Clement, John J.},
title = {Effects of Student Generated Diagrams versus Student-Generated Summaries
on Conceptual Understanding of Causal and Dynamic Knowledge in Plate Tectonics},
journal = {Journal of Research in Science Teaching},
year = {1999},
volume = {36},
number = {1},
pages = {39--53}
}
Current education practices in science domains at all grade levels utilize diagrams as adjuncts to the use of text for conveying concepts. Despite the current trend in education to more actively involve the student in the learning process, diagrams are used in a passive manner. When the diagrams are used as illustrative adjuncts to the text, they facilitate recall and comprehension, but for the goal of higher level, conceptual understanding, the explanatory role for diagrams does not adequately assist the student.
The authors conducted a study to determine whether a more active participation by students in constructing diagrams would aid in concept understanding. Their study built upon earlier research, in particular (Schwartz, 1993), but went further in assessing whether the construction of diagrams would improve comprehension.
The field of study chosen for the research was the domain of plate tectonics. This difficult topic offers a rich range of information such as the hidden layering of the earth's interior, as well as the causal movements within these layers. Two types of knowledge would be needed to be acquired (spatial/static and causal/dynamic) to generate a conceptual model of the workings of the earth's interior which resulted in such effects as earthquakes, volcanoes, and mountain formation. A text was utilized as the learning resource, with the text comprehension framework modeled on that of van Dijk and Kintsch (1983).
The participating Grade 5 students( 58 from three classes) were given a short text (two pages) on plate tectonics. One class, the control group, only read this text. A second group was instructed to make a summary of the concepts explained in the text at specific points as they read it. A third group was instructed to make diagrams of the concepts. Four diagrams and four summaries were requested. The points at which the diagrams or summaries were requested were identical for both these groups and care was taken to instruct them in what they were to do in as similar a manner as possible.
After completing the reading of the text and the applicable tasks where required (diagrams and summaries), all students were given a question booklet consisting of multiple choice questions, short answer questions, and diagram tasks. The purpose of the question booklet was to assess the students' knowledge of the spatial/static or causal/dynamic aspects of the domain. Data was gathered from the results of all students' question booklets. Additionally, for the non-control groups, the four diagrams/summaries prepared by the students were scored individually for inclusion of the main features/points.
For the intermittent data gathered on the non-control groups, multivariate analysis of variance was used. Two groupings of the data were used, the first grouping was individual tasks, while the second grouping was by type of knowledge (spatial/static versus causal/dynamic). In each grouping the results were the same - the group making summaries was scored higher than the group making diagrams, although the difference was marginal.
For the other set of data gathered from the question booklet scores, all three groups participated. The result was that the control group scored lowest, the summary group scored the intermediate result, and the diagram group scored highest.
The results of the research led to a discrepancy in that the summary group out-performed the diagram group in the scoring of the individual tasks, but the opposite result was shown in their rankings in the question booklet scores. This discrepancy was attributed by the authors to the type of knowledge learned in the two methods. In the summary group, the principal knowledge gained is domain-related information and its similarity to the text source of the information gave this method an advantage over the diagram group. In the question booklet, however, the knowledge sought was higher level, conceptual understanding that the making of diagrams reinforced and gave greater depth to. The higher scores obtained by the diagram group was the result of processing the text in a more complex, varied manner. The authors concluded that their hypothesis, that " ... the task of generating diagrams while reading would promote richer mental model construction than the task of generating summaries or simply reading the text" (p. 48) was supported. As a consequence, they suggest that "drawing to learn" (p. 49) may be effective in domains where processes cannot be directly observed, such as plate tectonics. This implies that science education may profitably include students making diagrams as a concept-learning technique.