The Student-Centered Classroom

A large part of the AAAS document, Vision and Change in Undergraduate Biology Education is devoted to how to teach science. The "core concepts" take up only 2 pages out of 79 pages in the booklet.

The modern buzzword phrase for the 21st century is "The Student-Centered Classroom" and "Student-Centered Learning." The terms means lot of different things to different people but the key concept is to move away from lecturing about "facts" to a classroom format that emphasizes student participation in the learning process.

Although the definition of student-centered learning may vary from professor to professor, faculty generally agree that student-centered classrooms tend to be interactive, inquiry driven, cooperative, collaborative, and relevant. Three critical components are consistent throughout the literature, providing guidelines that faculty can apply when developing a course. Student centered courses and curricula take into account student knowledge and experiences at the start of a course and articulate clear learning outcomes in shaping instructional design. Then they provide opportunities for students to examine and discuss their understanding of the concepts presented, offering frequent and varied feedback as part of the learning process. As a result, student-centered science classrooms and assignments typically involve high levels of student–student and student–faculty interaction; connect the course subject matter to topics students find relevant; minimize didactic presentations; reflect diverse aspects of scientific inquiry, including data interpretation, argumentation, and peer review; provide ongoing feedback to both the student and professor about the student’s learning progress; and explicitly address learning how to learn.

This is a very good idea in theory but putting it into practice is much harder than it looks. I've seen some excellent examples of student-centered learning at various conferences over the past few years. One type of student-centered learning seems particularly attractive to me and I've tried it several times in my courses. Here's how it's described in the Vision and Change document (p. 26).

Typically, these strategies engage students more actively in every aspect of their learning and are interactive, inquiry driven, cooperative, and collaborative, allowing students to engage with each other and with faculty. For example, the “problem–based model of instruction,” or learning cycle (Bybee, 1997; Fuller, 2002), revolves around a series of related questions that first probe what students know about a topic and then move to unfamiliar, new ground, enabling the students to develop a more complete and accurate understanding of the topic. Faculty initiate student interactions with key guiding questions and opportunities for discussion, present a short explanation of the necessary background knowledge, and then have students work together on questions to deepen their understanding through reflection on and application of their knowledge (e.g., Ebert-May et al., 1997). This approach incorporates frequent informal assessment (e.g., Angelo and Cross, 1992) to address misconceptions and provides a balance between direct instruction and student interaction. One or two class sessions using this approach to introduce a topic such as evolution might unfold in the following way (e.g., Ebert-May et al., 2008):

1. Engagement Question: For example, “What is evolution?” This background question probes student knowledge of the topic.
2. Exploration: Students share their answers with other students sitting nearby and come to a consensus; volunteers from the groups share their answer with the class, allowing the instructor to listen for misconceptions and depth of understanding.
3. Explanation: The instructor presents a short interactive lecture (15 minutes) on the topic, providing explanations to help clarify student thinking based on identified misconceptions.
4. Extension Question: Students work together on a more advanced question that might, for example, call for them to analyze information, formulate critical questions and hypotheses, evaluate and criticize evidence, or propose alternative solutions. In the example of evolution, the extension question, tied to a learning goal, might be What mechanisms are involved in natural selection, and what role does natural selection play in antibiotic resistance in bacteria today? Again, groups are called on to explain their answers and how they came to them.
5. Quiz Question: The final assessment (which may or may not be formally graded) allows both the student and the instructor to chart the effectiveness of teaching and learning.

The idea here is to confront misconceptions by having students come up with their own ideas about answering the "engagement question." This gives the instructor the opportunity to correct the most common misconceptions. In this example, the students will almost certainly come up with a definition of evolution that requires natural selection and excludes random genetic drift. They will frequently include mutation and recombination as part of their definition. Most of the time students will demonstrate lack of knowledge of population genetics.

The lecture component will explain the reasoning behind different definitions of evolution and why one might prefer one definition over another. Part of the explanation involves creating a "minimal definition" of evolution that will allow one to distinguish between evolution and something else. (I choose human examples. Think about the increased height in Europeans over the past 500 years. Is that evolution? Why or why not? Why do some native North American populations have only O-type blood? Is that evolution?)

The "extension question" should be designed to challenge students to think about the topic in new ways. In my case, the extension question is often something like this ...

If evolution is defined as a change in the frequency of alleles in a population and if fixation of alleles can occur by several different mechanisms, then what is the most common mechanism of evolution according to the data we have?

I think the three most important criteria in science education are (1) accuracy, (2) accuracy, and (3) accuracy. Everything else is of lesser importance, including how you teach the concept. Thus, you may be an expert at student-centered learning but if you don't understand evolution then the exercise is completely ineffective no matter how much the students may enjoy it.

If we are going to fix undergraduate education in biology then we need to concentrate above all else on making sure we accurately identify the core concepts and make sure they are being taught correctly. We can move on to other things once we are convinced that the first three objectives (accuracy, accuracy, and accuracy) are being achieved. It could actually be harmful to develop a student-centered learning course based on false concepts.

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