Candace Chick is the first to admit that she’s not an expert in science. Far from it, the teacher at the Samuel W. Mason Pilot Elementary School in Roxbury, Mass., only took one basic science class during her undergraduate and graduate studies and, until recently, quaked at the idea of teaching the properties of matter to her fifth-grade students. “I have always been insecure about science,” she says. “It is not one of my strengths.”
But now, she is positively ebullient about the progress both she and her students have made in the subject. Her class has been investigating molecular change, conducting hands-on experiments, and watching computer simulations. The students’ knowledge has grown deeper than simply being able to define terms like “condensation” and “evaporation.” They readily discuss their ideas and frequently engage in polite, intellectual arguments that influence each others’ learning. “Their knowledge isn’t, ‘Oh, there is a puddle on the sidewalk and when the sun comes out it evaporates and goes magically into a cloud and then it comes down again when it rains,’’’ Chick explains. “They understand how those molecules start to move and bounce around like mad as they evaporate. They really understand this in a way that they didn’t before.”
Chick’s class just completed the third year of a research endeavor called The Inquiry Project, a partnership between teachers, TERC, and Tufts University that teaches concepts like weight, volume, and density in grades 3–5 to lay the foundation for later introduction to molecular theory. In third grade, students begin exploring materials and then move on to investigating weight and volume, using density cubes and balance scales, among other tools. They proceed from comparing the “felt weight” of cubes made from different materials to measuring actual weight on a balance scale. They ask questions along the way. Can two objects of the same size weigh different amounts? Does a tiny piece of clay have weight? The students are asked to discuss their findings at every step: the goal of this “productive talk” is to lead to deeper understanding.
Chick worked with an Inquiry Project coach, who not only helped her overcome her inhibitions about science but also encouraged her to lead productive class discussions.
The goal is to shift the students’ way of thinking from what Anderson calls “force-dynamic reasoning” to what he terms “scientific discourse.” Force-dynamic reasoning, typical in elementary school, is a way of viewing the world in terms of “actors” with purposes. For instance, the main purpose of a tree (the “actor”) is to grow, and in order to grow, it needs water, air, sunlight, and soil. However, the scientific explanation is that the tree uses the sun as an energy source to convert carbon dioxide and water into glucose, which is the building block of the tree. “The scientific story is one of transformation of matter and energy,” Anderson explains. “If we are interested in preparing kids to think about carbon in our atmosphere and in our various environmental systems and how it effects global warming, we have to make the transition from force-dynamic reasoning to scientific reasoning, where they are thinking about matter and energy.”
The fourth-grade curriculum outlines a pathway toward that transition in thinking. It’s not about memorizing definitions of, say, photosynthesis, but about actually transforming how students think. Students begin by watching time-lapse videos of plants growing. They then grow plants under different conditions—with or without water and light. They measure the results over time and ultimately determine that plants need water, air, and light to grow. They then examine plants on a microscopic level and learn about their cellular makeup, which leads to an exploration of how plants make their own food and where they store it.
Through tending the plants and watching them grow, students can begin to view the plants not as actors, but as part of an ecosystem. Anderson and his colleagues are still generating data on what works, but the goal is for the students to understand basic underlying principles of science, such as conservation of matter and energy. “Facts alone,’’ he says, “are not enough.’’
Learning Progressions in Science
By PATTI HARTIGAN
Harvard Education Letter
Volume 26, Number 4
I'm wondering what exactly these 4th grade students know about photosynthesis at the end of the school year.