Monday, July 20, 2015

On "active learning" and teaching science

Nature ran an article last week by Dr. Mitchell Waldrop titled "Why we are teaching science wrong, and how to make it right" (or alternatively, "The science of teaching science") which really ground my gears.  The piece puts forward this growing trend of "active learning" where, rather than traditional lecture-based course instruction, students are put in a position where they must apply subject matter to solve open-ended problems.  In turn, this process of applying knowledge leads students to walk away with a more meaningful understanding of the material and demonstrate a much longer retention of the information.

It bothers me that the article seems to conflate "life sciences" with "science."  The fact that students more effectively learn material when they are required to engage with the information over rote memorization and regurgitation is not new.  This "active learning" methodology may seem revolutionary to life science (six of eight advocates quoted are of the life sciences), but the fact of the matter is that this method has been the foundation of physics and engineering education for literally thousands of years.  "Active learning," which seems to be a re-branding of the Socratic method, is how critical thinking skills are developed.  If this concept of education by application is truly new to the life sciences, then that is a shortcoming that is not endemic throughout the sciences as the article's title would suggest.

The article goes on to highlight a few reasons why adoption of the Socratic method in teaching "science" is slow going, but does so while failing to acknowledge two fundamental facts about education and science: effective education takes time, and scientists are not synonymous with educators.

I have had the benefit of studying under some of the best educators I have ever known.  The views I express below are no doubt colored by this, and perhaps all of science is truly filled with ineffective educators.  However as a former materials scientist now working in the biotech industry, I have an idea that the assumptions expressed in this article (which mirror the attitudes of the biologists with whom I work) are not as universal throughout science as Dr. Waldrop would have us think.  With that being said, I haven't taught anything other than workshops for the better part of a decade, so the usual caveats about my writing apply here--I don't know what I'm talking about, so take it all with a grain of salt.

Effective education takes time

The article opens with an anecdote about how Tammy Tobin, a biology professor at Susquehanna University, has her third- and fourth-year students work through a mock viral outbreak.  While this is an undoubtedly memorable exercise that gives students a chance to apply what they learned in class, the article fails to acknowledge that one cannot actually teach virology or epidemiology this way.  This exercise is only effective for third- and fourth-year students who have spent two or three years obtaining the foundational knowledge that allows them to translate the lessons learned from this mock outbreak to different scenarios--that is, to actually demonstrate higher-order cognitive understanding of the scientific material.

As I said above though, this is not a new or novel concept.  In fact, all engineering and applied sciences curricula accredited by ABET are required to include a course exactly like this Susquehanna University experience.  Called the capstone design component, students spend their last year at university working in a collaborative setting with their peers to tackle an applied project like designing a concrete factory or executing an independent research program.  As a result, it is a fact that literally every single graduate of an accredited engineering undergraduate degree program in the United States has gone through an "active learning" project where they have to apply their coursework knowledge to solving a real-world problem.

In all fairness, the capstone project requirement is just a single course that represents a small fraction (typically less than 5%) of students' overall credits towards graduation.   This is a result of a greater fact that the article completely ignores--education takes time.  Professor Tobin's virus outbreak exercise had students looking at flight schedules to Chicago to ensure there were enough seats for a mock trip to ground zero, but realize that students were paying tuition money to do this.  In the time it took students to book fake plane tickets, how much information about epidemiology could have been conveyed in lecture format?  When Prof. Tobin says her course "looked at the intersection of politics, sociology, biology, even some economics," is that really appropriate for a virology course?

This is not to say that the detail with which Prof. Tobin's exercise was executed was a waste of time, tuition dollars, or anything else; as the article rightly points out, the students who took this course are likely to have walked away from it with a more meaningful grasp of applied virology and epidemiology than they would have otherwise.  However, the time it takes to execute these active learning projects at such a scale cuts deeply into the two- or three-year curriculum that most programs have to provide all of the required material for a four-year degree.  This is why "standard lectures" remain the prevailing way to teach scientific courses--lectures are informationally dense, and the "active learning" component comes in the form of homework and projects that are done outside of the classroom.

While the article implies that homework and exercises in this context are just "cookbook exercises," I get the impression that such is only true in the life sciences.  Rote memorization in physics and engineering is simply not valued, and this is why students are typically allowed to bring cheat sheets full of equations, constants, and notes with them into exams.  Rather than providing cookbook exercises, assignments and examinations require that students be able to apply the physical concepts learned in lecture to solve problems.  This is simply how physics and engineering are taught, and it is a direct result of the fact that there are not enough hours in a four-year program to forego lecturing and still effectively convey all of the required content.

And this is not to say that lecturing has to be completely one-way communication; the Socratic method can be extremely effective in lectures.  The article cites a great example of this when describing a question posed by Dr. Sarah Leupen's to her students:  What would happen if the sensory neurons in your legs stopped working as you were walking down the street?  Rather than providing all of the information to answer the question before posing the question itself, posing the question first allows students to figure out the material themselves through discussion.  The discussion is guided towards the correct answer by the lecturer's careful choice of follow-up questions to students' hypotheses to further stimulate critical thinking.

Of course, this Socratic approach in class can waste a tremendous amount of time if the lecturer is not able to effectively dial into each student's aptitudes when posing questions.  In addition, this only works for small classroom sizes; in practice, the discussion is often dominated by a minority of students and the majority simply remain unengaged.  Being able to keep all students engaged, even in a small-classroom setting, requires a great deal of skill in understanding people and how to motivate them.   Finding the right balance of one-sided lecturing and Socratic teaching is an exercise in careful time economics which can change every week.  As a result, it is often easier to simply forego the Socratic method and just deliver lecture; however, this is not always a matter of stodginess or laziness as the article implies, but simply weighing the costs given a fixed amount of material and a fixed period of time.

"Active learning" can be applied in a time-conservative way; this is the basis for a growing number of intensive, hands-on bootcamp programs that teach computer programming skills in twelve weeks. These programs eschew teaching the foundational knowledge of computer science and throw their students directly into applying it in useful (read: employable) ways.  While these programs certainly produce graduates who can write computer programs, these graduates are often unable to grasp important design and performance considerations because they lack a knowledge of the foundations.  In a sense, this example of how applied-only coursework produces technicians, not scientists and engineers.

Scientists are not always educators

The article also cites a number of educators and scientists (all in the life sciences, of course) who are critical of other researchers for not investing time (or alternatively, not being incentivized to invest time) into exploring more effective teaching methodologies.  While I agree that effective teaching is the responsibility of anyone whose job is to teach, the article carries an additional undertone that asserts that researchers should be effective teachers.  The problem is that this is not true; the entanglement of scientific research and scientific education is a result of necessity, and the fact of the matter is that there are a large group of science educators who simply teach because they are required to.

I cannot name a single scientist who went through the process of earning a doctorate in science or engineering because he or she wanted to teach.  Generally speaking, scientists become scientists because they want to do science, and teaching is often a byproduct of being one of the elite few who have the requisite knowledge to actually teach others how to be scientists or engineers.  This is not to say that there are no good researchers who also value education; this article's interviews are a testament to that.  Further, the hallmarks of great researchers and great educators overlap; dissemination of new discoveries is little more than being the first person to teach a new concept to other scientists.  However, the issue of science educators being often disinterested in effective teaching techniques can only be remedied by first acknowledging that teaching is not always most suitably performed by researchers.

The article does speak to some progress being made by institutions which include teaching as a criteria for tenure review.  However the notion of tenure is, at its roots, tied to preserving the academic freedom to do research in controversial areas.  It has little to do with the educational component of being a professor, so to a large degree, it does make sense to base tenure decisions largely on the research productivity, not the pedagogical productivity, of individuals.  Thus, the fact that educators are being driven to focus on research over education is a failing of the university brought about by this entanglement of education and research.

Actually building a sustainable financial model that supports this disentangling of education from research is not something I can pretend to do.  Just as effective teaching takes time, it also costs money, and matching every full-time researcher with a full-time educator across every science and engineering department at a university would not be economical.  However just as there are research professors whose income is derived solely from grants, perhaps there should be equivalent positions for distinguished educators who are fully supported by the university.  As it stands, there is little incentive (outside of financial necessity) for any scientist with a gift for teaching to become a full-time lecturer within the typical university system.

Whatever form progress may take though, as long as education remains entangled with research, the cadence of improvement will be set by the lowest common denominator.