Everyone Says Lecturing Doesn't Work.
Does That Mean I Should Never Do It?
An excerpt from Learner-Centered Astronomy Teaching: Strategies for Astro 101
Slater, University of Wyoming; & Adams, Montana State University
Given the substantial research showing that lecturing is highly ineffective in promoting deep learning, why should anyone who purports to talk about better teaching even discuss lecturing at all? In fact, if you attend professional development workshops for faculty or read articles about effective approaches to teaching, it is easy to take away the message that lecturing always constitutes bad teaching. Lecturing, a term often used very much in the pejorative, is often characterized as nothing more than a highly inefficient method for transferring the information in the lecturer's notes into the students'notebooks, often with no mental processing by the students. At its worst, the lecturer is portrayed as droning on in a dry monotone while the students, totally disengaged from the process, wondering only, "will this be on the test?" Admittedly, if this is your image of lecturing, then there is little here to defend. And yet, faced with a large class of students, what else can we do but lecture? The answer, we contend, is plenty. But we also contend that even in the most reformed classrooms there will still be some—perhaps even a significant amount of—lecturing. Lecturing is not inherently a bad thing. Used appropriately, lecturing can be an important tool in instruction and is likely to remain the foundation of most courses.
It will help if you remember this one basic notion : it's not what you do that matters, it's what the students do. There is nothing inherently wrong with standing at the front of the room and speaking clearly and eloquently to your class. What is worrisome is having a room full of students absently taking notes with little or no mental processing of the information while, too often, they are thinking about things completely unrelated to astronomy. It is not active bodies we are after but active minds. As long as students are thinking critically about the concepts being presented and attempting to integrate the new concepts into their existing knowledge, then at least the potential for meaningful learning exists. And, there is no reason why this cannot happen during a lecture—that's the good news. The bad news is that to rely solely on lecturing is to stack the deck against achieving the kind of deep learning for which we strive. To our dismay, research repeatedly shows that teacher-centered lectures have only a limited effect on student learning. For example, one classic study reported that only 66% of students showed signs of attention to lectures after 18 minutes, and no students were completely attentive after 35 minutes (Verner and Dickinson, 1967). All too often in our own classes, we look out into the crowd and find students reading newspapers, talking with one another, and, at times, blatantly sleeping with their heads on the tables. But more disturbing than a lack of paying attention during lectures, research suggests that student learning is poor even for those students who pay attention in class. In the context of reviewing learning gains of 6000 physics students, Hake (1998) reported that students attending lecture-based courses had far lower cognitive gains than those who attended classes characterized by some form of active-engagement.
So, with all this negativity, why lecture at all? In fact, there are a number of things that can you can do very effectively by lecturing:
- You can communicate your enthusiasm for the subject... As scientists, we do what we do because we have an insatiable curiosity and love for our subject. Lectures provide an opportunity to share the human side of science with students who, raised on media images of scientists, too often see science as a sterile and inhuman endeavor, devoid of the kind of personal creativity and passion that students normally equate only with the arts and humanities. If nothing else, displaying openly your personal passion for astronomy provides an opportunity to keep students motivated to read and complete assignments.
- You can present the newest, cutting-edge discoveries.. One of things that generally sets astronomy apart from most other sciences is the ravenous public enthusiasm for our latest discoveries (paleontology would be one notable exception). Though your students might not yet be at a point where they can fully appreciate the implications of the work, sharing recent discoveries creates a sense of excitement and interest. And, because you explain the discoveries in simple terms, students have something to share with friends and family. Whereas students are unlikely to talk to friends about how the H-R diagram can be used to estimate stellar distances, they are apt to talk about what they learned about the latest space mission. For non-science majors, this opportunity to share with others can be an empowering experience.
- You can share the stunning images that astronomy affords.. Astronomy is, or at least can be, a visually engaging subject and, every time you get to show your class the Hubble Deep Field image, aren't you thankful that you don't teach Calculus to non-majors? Many of the images that we show are in their textbooks, but these small textbook images do not have the same impact as when presented on a large screen accompanied by an enthusiastic description in the context of what is being studied.
- You can emphasize the important points from the textbook to help frame and guide students' reading.. Typical astronomy textbooks are full of information, but students have immense difficulty separating the details—those things that are interesting to read but not of critical importance—from the central message. For instance, isn't the primary message about the ISM its very existence rather than the details of its composition and the various means we have for detecting it? Lectures are ideal for providing needed focus and communicating what aspects are truly important.
Our thinking is not that you should avoid lecturing at all costs; rather, when you do lecture, you and your students should know why you are doing it. Most importantly, you should try to avoid uninterrupted lecturing (i.e., talking directly to the class) for more than 15 to 20 minutes without taking a short break to engage in a student-centered activity such as individual questioning, think-pair-share, talk-to-your-neighbor, in-class writing, or Lecture-Tutorials, just to name a few.
To find out more about these, and other, student-centered activities, check out the book Learner-Centered Astronomy or, better yet, attend one of our workshops.
Hake, R. R. (1998). Interactive-engagement versus traditional methods: A six-thousand-student survey of mechanics test data for introductory physics course. American Journal of Physics, 66(1), 64-74.
Slater, T. F. & Adams, J. P. (2003). Learner-Centered Astronomy Teaching: Strategies for Astro 101 (pp. 39-41). New Jersey: Prentice Hall.
Verner, C. & Dickinson, G. (1967). The lecture: An analysis and review of research. Adult Education, 17, 85-100.