Moving away from textbooks

As a professor charged with teaching science at an institution where there are no science majors, I cannot avoid thinking about how to make material accessible to my students. I don’t think that this is a bad thing. From my experience as a graduate student at a big research university, it seems that most professors perceive a big distinction between undergraduate majors and non-majors. I think this distinction has more to do with the needs of instructors than the needs of students; non-majors force instructors to present material in a clear, coherent manner (because non-majors lack the time, background, and perhaps motivation to create understanding on their own), whereas majors will make up the difference between the quality of instruction they deserve and the actual instruction they receive (because if they want to succeed in a particular major, they need to do so regardless of how well they are instructed). I realize this is a cynical viewpoint, but it is also a fairly positive one: I believe that the burden for building student understanding lies with the professor.

The material we ask our students to read forms an important basis for the teaching we do in class. Traditionally, the reading material of choice is a textbook. Increasingly, I am questioning the wisdom of using textbooks as a primary source of reading material.

My biggest objection to textbooks is that they are linear. All teaching is challenged by a fundamental problem: knowledge is networked, but instruction is linear. As teachers we must guide our students through a network of information which is often critically inter-related: no concept can be understood in isolation, and most concepts link to many other concepts (some of which may even lie outside the boundaries of a particular discipline). We teach across linear time, and our students usually read across linear pages (notwithstanding the potential for networked web-based readings), so there’s no way to avoid the mismatch between how we teach and what we are trying to teach. But textbooks often compound this problem because by nature of their physical, analog form they have to flow in a particular linear progression.

I think most instructors, even when they love a particular textbook, are frustrated by its linear nature. Whenever I teach a course using a textbook, I tend to re-arrange the order in which material is presented to match my sense of how best to walk linearly through the multi-dimensional space of understanding. This leaves students reading some chapters before preceding chapters, inevitably leading to the “as you read in Chapter X” problem associated with creating your own reading sequence from a textbook that assumes that it will be linearly read from cover to back. Textbooks create their own world and assume that you will follow their rules, and so (for the most part) present material once and in the order of the author’s choosing. Don’t like the order? The only solution is to work around it, or to get another textbook.

Or, alternatively, you can simply get rid of the textbook altogether. This is increasingly what I prefer to do for my courses. Rather than assign chapters from a textbook and structure the course around the linear progression of the textbook, I instead begin by deciding what order of presentation makes most sense in light of my educational goals. Once this map is created, I then find stand-alone articles that illustrate the concepts I want to cover during each class session. Although this can be more time-consuming, it is usually more valuable to students. Stand-alone articles take on the burden of placing the focal concept in context, and thus inherently build up connections to other topics. Taken as a whole a collection of articles also provide students with multiple perspectives rather than the singular vantage-point of a particular author or small group of authors. And because articles are constantly being published to report on the most recent findings, older articles can be swapped out for newer ones. The use of learning management systems like Moodle makes this mode of delivery even more easy, as students can download individual articles from course sites accessible only to enrolled students.

A great example of an article that far exceeds the value of a textbook chapter appeared in the April 2010 issue of Scientific American under the title “The Hidden Life of Truffles”. I plan to assign this article to support an Ecology lecture I give that describes the role of different kinds of organisms in ecological cycling: this will be my entry point into the world of fungi and their role as decomposers in ecosystems worldwide. But because this article needs to stand on its own (rather than simply referencing concepts in other chapters of a larger text), it explicitly links to other ecological and evolutionary concepts that I teach before and after explaining decomposition. Nested in the text are examples of mutualistic symbiosis, consumer-resource dynamics, evolution in response to abiotic factors, chemical signaling, evolutionary convergence, and dispersal of offspring. If these are concepts I have already taught, they will remind my students of what they have learned, reinforcing early examples of specific concepts. For concepts that I have yet to teach, the introduction of these ideas through this article primes students for later understanding. Unlike a textbook chapter, the article provides students with a more holistic understanding of the topic at hand.

I think that the main difference between a course for majors and non-majors should center on what articles are assigned. Because scientific publications require that authors place their specific study in context through their introductory content, I have found that students can gain “networked understanding” from primary literature articles. As suggested with the example above, popular scientific articles also have the potential to provide students with far greater understanding than stand-alone textbooks. Perhaps it seems obvious that non-majors should receive the popular science articles and majors should receive the articles from the primary literature, but I would argue that the distinction is more about the mix: non-majors do benefit from an occasional reading from the primary literature, and many popular science articles are simply too well-written to deprive majors of their benefits.

With all this said, I still use textbooks in several of my classes. Often, I would describe my own adoption of textbooks as a “necessary evil”. In some cases, I simply cannot pull together enough articles to cover all the concepts that I want to incorporate into my class. In this sense, textbooks sometimes have the advantage of being more comprehensive than any collection of articles. Choosing a textbook is also easier to do quickly, whereas collecting appropriate articles can take months and is probably best done passively (collecting articles as one encounters them in new literature) rather than actively (trying to find articles that work via massive literature searches). In some cases, I have endeavored to teach subjects that I simply don’t know enough about (at least at the outset) to avoid using a textbook. So adopting a textbook is a compromise, and sometimes a necessary one.

A good textbook does recognize that the understanding it seeks to build is networked. The best textbooks provide “links” in the margins of chapters to other chapters, providing students with the opportunity to connect with concepts they have already read about and concepts they will soon read about. But the inevitable linearity of paper textbooks makes this a meager solution. Publishers have picked up on this fact, and have in some cases tried to address student and instructor needs by making custom textbook creation possible. The best example I know of such technology is McGraw-Hill’s CREATE program. But such programs are really trying to patch up the textbook problem through simple rearrangement. I don’t think this is enough: the nature of what constitutes a “chapter” is what needs to change. Chapters need to stand alone, not just be reordered.

Eventually, I think that all textbooks will be electronic in some form. This flows not only from the switchover we are seeing from paper to screen (facilitated by various forms of “reader hardware”) but also from the need for more holistic teaching that builds networked understanding. A truly valuable textbook would be one that presented a series of stand-alone articles designed to be incorporated in a clearly-delineated concept map. Based on the network of conceptual connections built up between these articles, instructors would be able to choose their own linear “walk” through the multi-dimensional map of ideas created by a particular subject. At each “stop” (a particular article) along this walk, students would be given not just a view of a particular location but also how that location connects with places they have already visited and places they will soon visit.

Until such a resource exists, I cobble together my own using articles pulled from a myriad of sources and create my own “network of understanding”. I think my students prefer this way of teaching, and benefit more from its variety and intentional redundancy.