A long-term goal for the nation is to find teaching strategies for developing deeper understanding of science topics in schools. This two-year study examined strategies teachers use for leading class discussions to support conceptual understanding in science, with a particular focus on scientific models. We also investigated the role of whole class discussion when using computer simulations to support learning.
Modern research-based curriculum units provide well thought-out strategies at the one-hour lesson plan level. However, we lack transparent descriptions of minute-by-minute strategies that successful teachers use adaptively in leading whole class discussions. This project used video case studies to identify key strategies used by exemplary teachers to guide class discussions. The project studied teachers in the areas of high school electricity and middle school life sciences, and was designed to help us identify and describe key discussion-leading strategies.
This study showed that teachers use a variety of strategies, and may use several strategies at once to achieve multiple goals while teaching. Some of these strategies aim to keep students talking and contributing to the discussion, while others are aimed at facilitating specific kinds of student cognition. The project identified 19 such cognitive strategies.
Computer simulations are increasingly used in science classrooms and may help students learn abstract models. We conducted a study that compared middle school classes using static overhead projections with matched classes using an animated simulation that was projected and run in front of the class. The study involved 222 students. The classes using simulations did significantly better on tests of conceptual understanding. An analysis of teacher behavior suggested that the simulation mode may have offered greater opportunities than the overhead mode for planning and enacting discussions. The study also offered new descriptions of teaching strategies used during the discussions of simulations.
Another study found that groups studying computer simulations or animations in whole class discussion format did as well or better than those studying the same displays in small groups, suggesting that both modes may be important for instruction. An implication is that, although most teachers expect the small group format to foster more active learning, some combination with whole class discussions is probably best, especially where students may miss, or misunderstand, visual aspects of the computer simulations.
The above projects were aided by an ongoing study of data on learning processes employed by expert scientists when they are asked to explain an unfamiliar system, with an emphasis on the roles of analogy, imagery, and thought experiments. Describing their learning processes has helped us formulate new descriptions of scientific practices that can also help describe student learning in science.
We assembled collections of the strategies that the teachers in these studies used, and developed new techniques for diagramming discussions to help teachers envision the strategies. The strategies and examples identified were then piloted in teacher education courses. We were able to measure positive changes in prospective teacher's beliefs about the role of discussions in science classes in this pilot. Descriptions of the strategies are being disseminated to teachers via a website on discussion-leading strategies for building models using computer simulations, accompanied by real classroom examples.