Blackboards and Whiteboards: How to Enhance Working Memory While Running Class Discussions

Instructors and students face much heavier cognitive demands in discussion-based class sessions than in more straightforward lecture or structured discussion classes. They face the problem of managing their working memory: being able to hold multiple elements in their minds while actively processing them. In this post, I offer some strategies for easing the burden on working memory by externalizing much of the discussion.

Photo by Robina Weermeijer on Unsplash
Brain bits, from Photo by Robina Weermeijer on Unsplash

Free flowing discussions enliven classrooms and make college teaching gratifying for instructors and students. Unlike lectures, which tend to be heavily scripted and lacking in spontaneity, discussions allow students to actively participate in the process of generating, elaborating on, and assessing new knowledge. Hidden assumptions are surfaced, risky positions are staked out, and instructors must be on their toes to keep up with students. When run well, discussions move students from passive consumers of content generated by instructors to active participants in a collective learning effort. Discussions can reward students by validating their voices and showing them that their point of view is shared by others, something that’s often invisible to students in lecture classes.

However, the free-flowing spontaneity and uncertainty sparked by classroom discussions poses problems for instructors and students alike. For instructors, their role switches from almost ironclad control of the pace and content of class sessions to one of managing multiple threads in what can be chaotic conversations. Rather than proceeding in stepwise fashion through a set of lecture notes, instructors who pose open-ended questions to their students must be prepared to play more of a “traffic cop role.” They must keep track of multiple threads in the conversation, deciding when a line has played itself out and when a new line should be pursued. They must remember what previous commentators have said so that they can point out complementarities and contradictions and possibly direct questions back to the original speakers.

Similarly, for students, participating in in discussions rather than simply answering questions with fixed answers raises their level of interdependence with fellow students. To participate effectively, they need to pay attention to others’ contributions so that they know whether their intended point is still relevant or if the conversation has moved on. If they spend too much time thinking about an original contribution they want to make, they may miss the opportunity to build on what has already been said by another student. As more lines of inquiry are opened in the discussion, they need to remember how the discussion all began and the diverse lines of inquiry that may have developed.

In such uncertain circumstances, everyone involved struggles with managing the cognitive load placed on their working memory. How can they hold multiple elements in their minds while actively processing them? The issue is not about getting things into short-term memory, which is also something that could be happening during the discussion, but rather one of juggling the diversity of elements that have arisen so that they can make good decisions on things like turn-taking, closing lines of argument, and preventing incivilities that can derail discussions. Effective participation requires skill in managing short-term memory, and that skill differs so much across individuals that it can skew the distribution of participation, if instructors don’t know how to manage the discussion. Trying to keep matters straight solely through juggling all components in working memory can be a recipe for disaster.

Fortunately, instructors have a simple technology that makes it easier for them and their students to manage working memory: the blackboards, SmartBoards and whiteboards in their classrooms. Of course, many instructors still buy whiteboard products too because the majority of classrooms have whiteboards to help the instructor explain to the students in further depth. To teach, instructors only need a piece of chalk, a felt-tipped marker, or an electronic wand to get the conversation started. Using a blackboard or other visible recording device enables instructors to externalize much of the conversation, making the question and key lines of argument observable by students, thus reducing the cognitive load on working memory.

Here are some simple tactics. First, the initial question should either be written on the board or handed out on a sheet of paper so that students can refer to it throughout the conversation. They shouldn’t have to ask the instructor to repeat the question, once the discussion gets underway. Second, they should clearly label columns on the board in which they are going to record answers, and decide whether they will use words, phrases, or try to write entire sentences. It’s crucial to label the columns if there is going to be a debate among multiple positions during the discussion. Third, to show students that their views are being taken seriously, comments should be written on the board in the student’s own words, rather than in condensed form. If a student says so much that instructors feel the need to edit, then they should ask the student’s permission before writing up their own version of what was said. If the class is small enough, instructors might also consider putting a student’s initials next to the points they make, so that they can return to their comments for clarification later in the discussion.

Fourth, instructors should take advantage of the breaks allowed in the conversation while they are writing to step back occasionally and look over what has been written on the board. Look for undefined terms and concepts or contradictions, because of students’ differing opinions. At that point, or at another designated time during the conversation, call attention to the gaps and ask students what to do. Ideally, instructors should not do this themselves! Ask the students to do it first. Only after students have had a turn should instructors offer their own views on definitions and reconciliations.

Used in this fashion, keeping track of the discussion through writing on the board reduces the cognitive load on working memory for both instructors and students. Students can concentrate on responding to the question on the floor in the moment, rather than having to keep in mind all that has happened up to that point, particularly when their peers have offered contradictory views. By stepping back and pausing occasionally, instructors can get a sense of the flow of the conversation, whether it is cumulative, and whether additional follow-up questions should be brought into the discussion.

I use this teaching strategy when I don’t have a fixed set of points I wish to make and when I want to see how facile students have become at taking what they have already learned and building on it. Often, their contributions take us off in directions that I have not anticipated. Keeping track of the conversation on the board relieves me of many of the difficulties of managing open-ended discussions, which at the hands of an unskilled discussion leader can often lead to chaos and ambiguity in the closing moments of the session. In a sense, I have externalized many of the “traffic cop” functions and can concentrate on the more substantive side of helping students probe more deeply into understanding what their peers are saying.  It also frees me to spend more time on finding ways to get more students involved in the conversation.