Sixth graders are immersed in the science of simple machines, which means that Cat Blakelock’s classroom is the scene of flying marshmallows, bottles of glue, loads of popsicles, and frequent shouts out of discovery. Girls trek around campus measuring stairs and plotting data on graph paper.
The essential questions at the heart of all of these lessons are related energy and effort: How can we use tools and our knowledge of physics to lift, move, carry, or fling an object from one place to another? What data do we need to know in order to build a contraption that will reduce our effort? What calculations will help us be efficient and effective?
The unit started with levers. Although most of the students had some familiarity with a simple balance lever, Ms. Blakelock introduced the idea that levers can be organized into different types, depending on where the load and effort are located. For one of their first research assignments, girls brought home a list of objects and assigned them to categories: Hammers, wheelbarrows, pliers, shovels, scissors, brooms, fishing rods…all of these familiar items are examples of levers in action.
One of the most dramatic kinds of lever is the catapult. This powerful application of physics involves placing a load at one end of an arm that is under pressure, then releasing the pressure and allowing the arm to propel the load through the air. In sixth grade science, the “load” was a mini marshmallow, the arm was a plastic spoon, and the pressure was generated from a rubber band. Basing their designs on the knowledge they had gained from their lessons, teams of girls built contraptions with carefully positioned popsicle sticks and glue. On the day I visited, the excitement was palpable, as was the collaborative spirit among the students.
As I circulated around the room, girls shared their designs: “we have a long arm on ours, because we think it will send the marshmallow farther,” one student told me, emphasizing the word “we.” She and one of her partners then drew a diagram to explain their thinking to me. “Last week, I did not know all of these terms,” one of the girls mused. “Now, I really understand it!” Another team was concentrated on building a tall base so that the spoon would be perched several inches high. They carefully carried their catapult to an area of the floor that was marked with tape. “I think we should measure it from here,” one girl suggested. She and her teammates conferenced for a few minutes, deciding exactly where to place their base. Everyone contributed to the preparation and the precise setup. The rubber band was released, the marshmallow flew, and two budding physicists leaped to measure the distance it had traveled. Immediately, they set up the catapult for another attempt. “the more results we have, the more certain we can be about our design,” a student told me confidently.
The scene in the classroom highlighted for me, once again, the benefit of a girls’ school. Here were teams of four students gathered around their projects. They offered ideas, listened to each other, agreed, disagreed, tried something, tried something else, laughed, measured and recorded data, and worked toward a common goal. Yes, this type of group work occurs in co-ed classes, but often it is the loudest voice or most assertive team member who takes the lead—and often, it is not the girls who are the loudest or most assertive in these settings.They are eager to build from each other’s suggestions, share frustration when an attempt doesn’t work and celebrate together. Here at Dana, girls are the leaders, thinkers, and idea generators.