I don’t normally blog about anything happening in a class during the semester because I don’t want students thinking that anything they say will end up here, but this I must post. As I say in my profile, I write this not because I think anyone will be interested – in fact I am sure that this will be boring as all hell. I write here because writing helps me organize my thoughts and because this is a “public space” I tend to want to be more precise with my words here. So with that excellent spiel I urge you to stop reading here.
Its difficult for me to teach to people I don’t know. I could have a bunch of slides ready and just start bashing through those (lord knows there are enough factoids in Microbiology to do go that route), but that is boring and more importantly, somewhat inefficient educationally. That would be the “I fill them up with knowledge” philosophy, which makes me want to shove pencils through my eyes. They are all capable of reading the book – I am not there to recite. In fact given that people read much faster than I can talk, that doesn’t seem like an efficient use of our class time. My role as a teacher is to help with the material that I know from experience, and from asking these students in front of me questions, is difficult for them. They have misperceptions. Building knowledge on top of these misperceptions would be a bad idea. They think that “infection” and “disease” are almost the same word, when in fact most of the organisms that infect you will NEVER cause disease (Google: Human Microbiome Project). They aren’t really sure that all living organisms are cellular. They think that Science has the answers to most questions about infectious disease and completely miss the point that the answers aren’t important, its the questions that are. This isn’t a value judgement on these students, I find that their microbiological misperceptions are reflective of the misperceptions of the general public. Why would they have ever had to think about whether all life is cellular? Where would distinguishing the words “infection” and “disease” really be all that critical in every day life for them so far?
So the first week of class I go slowly and try to create an environment where as many students as possible feel comfortable exposing themselves a little, comfortable asking questions that might make them a little uncomfortable. I remind myself that they are in an educational system that puts an emphasis on the retention of facts (as was I), that they have been coached to look for “right answers” and not necessarily to ask deep questions (although they clearly can and sometimes do).
On Tuesday I wrote “What is a microbe?” on the board and then drew the Domains and Kingdoms of taxonomy. I didn’t call it taxonomy, I emphasized that these were nested boxes and that every organism on the planet could be put into one of them. I really had one goal: to lead them towards the conclusion that when they had learned the facts about “human cells” in first semester Anatomy & Physiology* what they were really learning was the facts about Plasmodium falciparum, the parasite that causes malaria, the facts about the cells of a tapeworm, that what they had learned had gotten them more than half way to a decent understanding of the replication of Herpesviruses, that most of the basic concepts about cells and cell biology they learned also apply to Bacteria.
The questions on my feedback sheets from Tuesday were excellent – the usual questions about class logistics (answered online) and then many questions that went deeper. Several pointed out that I never actually answered my question “What is a microbe?” (this had been intentional), so on Thursday I brought the feedback sheets in and answered a few content questions and then brought up that I had never answered my original question. What I wrote was not an important question, I said. Then I re-wrote the Domains and Kingdoms and circled all the categories that had “microbes” in them (all but plants). My point was that to say an organism is a “microbe” tells you very little about it, but to say that it is a bacteria, or a fungus, or a protist or an animal – THOSE are valuable terms that carry a lot of information.
After “covering” a bit of disease versus infection, of normal microbiota versus transient microbiota, I stopped and wrote the following on the board:
What do you think is the closest approximation of bacterial cells to eukaryotic cells in the average, healthy human body?
A. 100:1 B: 10:1 C. 1:1 D: 0.1:1
I told them that none of these are exactly the right answer, that there is no one ratio for every person, that we can’t actually count cells like this, but that one of these is closer to the true value, and that I want to know what they FEEL is closest to the true value. I am not interested in the right answer here, in fact the right answer is meaningless, but which answer their gut tells them to pick (oh oh – pun!) tells me a lot about what they think the role of microbes in our lives is. After after answering questions about the question, and explaining what I meant by “ratio”, I let them think about it and then we did a vote by hand. As long as the question is interesting (and I am full of questions that are not interesting to the average student), I have found this to be a powerful way to get discussion going (especially in the questions about the question part). I ask them to commit to an answer and vote.**
They overwhelming picked A and B. On the surface, this would indicate that they appreciate the fact that there are more bacterial cells in your body than “human” cells. Before the vote however, one student indicated to me that the learning environment was comfortable by saying that she was leaning toward 100:1 because I (Jeff) “was so excited and this is a Microbiology course”. I tried to fend her off, saying that maybe I was doing that on purpose to mislead them – how could she be sure? (she was very sure, couldn’t get anything past her). After the vote I asked how many of them had taken into account what I as the instructor of a Microbiology course might think is the right answer, most raised their hands and admitted that they were trying to infer a “correct answer” out of my actions.
Most of them did get to the right answer (10:1), but this is kind of frustrating. Education brings me these really smart, well prepared, very motivated students who, when asked “what they feel might be correct” don’t trust that their feeling would have value. They don’t appear to think that they should be speculating or approximating answers. I suspect that they are conditioned to a classroom being a place were “correct answers” are doled out and of themselves as passive recipients of these “correct answers”.
This isn’t terribly disturbing to me, as the discussion afterword did show spunk, there were some good questions, some asking for clarification in the vein of “wait, that can’t be right”. I ended that segment of class very sage on the stage-like by saying something like: After taking two semesters learning about the eukaryotic cells in your body, welcome to the class where we will learn about the other 90% of your cells and what they are doing.
* – I am fortunate in teaching Microbiology at Georgia Perimeter College in that these students had to take one semester of Chemistry and two semesters of Anatomy & Physiology to get into my class. They might have microbiological misperceptions but they come well prepared, knowing more about Anatomy than I do (which isn’t all that hard) and they come motivated. I have a special love for this population of students.
** – To lower the blood pressure in situations like this, I tell them on the first day that I don’t cold call. If I ask a question and I don’t get an answer (or hear from the same two students) that tells me more about my failings in encouraging a comfortable learning environment than it does about “what they know” or are interested in. It could also mean that I have not asked a question that seems interesting to them, which is once again my fault because there are enough interesting questions in this field to pick from to illustrate any given concept. I also know that many students are introverted and become stressed when called out. Stress, I point out, defeats thinking like nothing else, and more than anything else, I want students to think in my class, not just to “receive knowledge”.
1/19/14 – I’m not normally keen on quoting the bible but there is nothing new under the sun. What I am describing in my class has been observed before. Particularly helpful is Women’s Development Theory where these students would probably be “received knowers”. When I first read about the WDT’s classification of learners (from Ken Bain’s “What the Best College Teachers Do“), it wasn’t called WDT. As I write this I am putting together that 90-95% of the students in my Microbiology course are young women trying to get into Nursing school. Lord knows I have had my troubles figuring out how the women in my life think, but I honestly have seen the women in my class as students first, not women. I should probably think about that. A scan of the WDT wikipedia entry has some interesting points, but I will read the book instead.