Teaching Matters: Turning the Teaching of Sciences Upside Down

April 18, 2010

Many colleges and universities pack new science majors into large lecture halls to teach them about science. In those classes, professors and students discuss how science is studied, but the chance for students to actually "do science" is reserved for late in the curriculum, if at all. Only rarely are students involved in an actual scientific study—where an answer to a given question isn't known by anyone, including the instructor—until they pass several prerequisite courses, usually with a required high mark.

About 10 years ago, my colleagues and I in the biology department at Grinnell College began to wonder whether there might be another way to teach science. Over the previous decades, introductory biology textbooks had expanded to arm-breaking size, with a corresponding growth in the number of required intro biology courses. In a deep, soul-searching moment, we began to seriously consider turning our curriculum upside down. What if we had students do research, real research, first and then filled them in on the details and the big picture later?

Such an approach promised many advantages. First, it would preclude the unfortunate but occasional reality of students discovering in their senior year that they are either inept or apathetic about serious scientific inquiry. Second, if we gave students the chance to do the real thing, some of them might discover a love for science that they didn't know they had. The third and most immediate advantage was the opportunity to alleviate our out-of-control curricular growth by recruiting students more explicitly into the process of managing their own biology education. It was our hope that once students experienced genuine science, they would appreciate the worth of a broad background in biology and its closely related disciplines such as chemistry, physics, and mathematics, and would take the initiative to seek out appropriate educational opportunities.

Last, but definitely not least, this upside-down curriculum would better serve the many students who take biology but have no intention of becoming scientists—those future philosophers, politicians, and poets who take biology to round out their liberal-arts experience and prepare themselves to be knowledgeable participants in 21st century.

In creating an inverted introduction to biology, we knew that such a course would require smaller enrollments than was typical, even by the standards of a small, private liberal-arts college. Despite Grinnell's larger-than-normal ratio of resources to student, we knew the change would require a much larger investment in our early curriculum. And given the amount of effort we were anticipating, the faculty had to be highly motivated to direct the research.

The solution that resulted was a course we call "Bio 150: Introduction to Biological Inquiry." Each of us in the department offers a section of Bio 150 that focuses on a specific, carefully chosen question or set of questions. Because the Bio 150 section that we teach is related to our own research, we are best able to guide students toward questions that are most likely to yield some answers.

Our first set of Bio 150 sections were offered in the 2000-1 academic year. Students could choose one (and only one) of the following seven sections: "Building an Animal," "Prairie Restoration," "The Language of Neurons," "Biological Responses to Stress," "Emerging and Re-emerging Pathogens," "The Effects of Climate Change on Organisms," and "What Does It Mean to Be a Plant?" Since then, we have added a few more sections to our repertoire, including "Sex Life of Plants," "Plant Genetics and the Environment," "Survivor," "Cell Fate: Calvin or Hobbes," "Genes, Drugs, and Toxins," and "Animal Locomotion."

Each section is limited to 24 students, the largest size that we can accommodate in our laboratories, where we spend most of our class time. In each course, the professor minimizes formal lectures, covering only essential background information. Most of the course time is spent learning to explore the scientific literature, choose good questions, and select the best means to answer them; developing a repertoire of techniques carefully selected by the instructor; actually doing the experiments; and finally analyzing, interpreting, and presenting the data in both written and oral formats. The course concludes with a combined poster session modeled after those at professional meetings, with students contributing posters (usually as part of a group of three students) that describe the original research.

This year will be the 10th time we offer Bio 150. Has it accomplished what we had hoped? One of our goals was to nip our curricular growth in the bud, and we have clearly succeeded there. After students complete Bio 150 and Intro Chemistry, those who want to take more biology are directed into a two-semester course sequence that rounds out their biology education. Although the sequence is similar to what we had previously offered in four semesters, there is now a key difference: the students. They now understand why they are learning about molecules, cells, organisms, and their ecological and evolutionary relationships. They understand because they have seen how all the parts contribute to a good, if not elegant, scientific study. The students also appreciate that biology is a fun and highly creative endeavor, and they demand no less from us in their subsequent courses. In fact, our greatest challenge as instructors is teaching the courses in our curriculum that follow Bio 150. Once we let the cat out of the bag, it was impossible to get it back in.

Our most important goal in creating a new curriculum was to make it possible for our students to experience biology through real research. However, it's not all pretty. Our students discover that the scientific method is difficult, slow, and sometimes tedious. Despite what is unintentionally suggested in textbooks—and even scientific papers—scientific progress is not always linear or unidirectional. It often moves in more than one direction at a time and sometimes even moves backward. And, when it moves forward, it almost always moves in small, almost imperceptible steps. In short, Bio 150 is painfully authentic.

In the words of one of our students, "Anyone who takes Bio 150 and still wants more is either crazy, born to be a biologist, or both." Mission accomplished.

Clark Lindgren is a professor of biology at Grinnell College.