Scientific investigations can take place over months and years in the K-8 grades, and when they are effective they can result in dramatic changes in the ways that students think about the topics they are studying, about their own thinking and learning, and about the enterprise of science. By actually looking at how their own thinking about a phenomenon has changed and developed, students see learning in action. In other words, they come to understand what it actually means to learn something—an understanding that is called for in Strand 3.
Like much of science learning, this kind of understanding will not evolve without intentional support from teachers and instructional materials. Reflecting on one’s own scientific knowledge is critical to the enterprise of science and science learning. Scientists integrate new knowledge gained through investigations only when that knowledge is examined in relation to what they already know, tentatively believe, or previously doubted. Children, like scientists, must learn to examine the history of their own thinking and revise it if necessary, in light of subsequent investigations.
To examine how effective teachers can teach students to reflect on their changing knowledge in this way, we visit the classroom of Sister Mary Gertrude Hennessey, a science teacher for grades 1-6 in a small, rural elementary school.
Sr. Hennessey understands that in order to reflect on knowledge over time, children require extended opportunities to work on critical scientific concepts. She systematically focuses her lessons on core ideas built cumulatively across the grades. She enables her students to think deeply about knowledge in two important ways: she guides them in thinking and talking about how the scientific community structures and develops knowledge, and she helps her students think deeply about their own thinking, or how to be “metacognitive.”
Research has shown that Sr. Hennessey’s sixth-grade students have a much better understanding of the nature of science than sixth graders from a comparable school. The table below shows the way both her role and her students’ roles change from first grade through sixth grade.
Here’s a look at Sr. Hennessey and her students in action:5
During a classroom demonstration in Sr. Hennessey’s first-grade classroom, a large, transparent container of water is placed on an overhead projector. Students are asked to predict what they think will happen when various objects are placed in the water. The objects in question are two stones—a small (2-centimeter diameter) granite stone, and a large (10-centimeter diameter) pumice stone. The students did not have the opportunity to handle the stones prior to the demonstration.
One student, Brianna, is called on to explain her predictions.
Sr. Hennessey: “Would anyone like to predict what he or she thinks will happen to these stones? Yes, Brianna?”
Brianna: “I think both stones will sink, because I know stones sink. I’ve seen lots of stones sink, and every time I throw a stone into the water, it always sinks.”
Sr. Hennessey: “You look like you want to say something else.”