Last year I taught middle school earth science at a local private school part-time. One of the things that immediately struck me was their attitudes on science. In particular, they were really hung up on finding out “the answer”. Eventually I was able to track this idea to their reliance on the scientific method — something that had been drilled into them for years. Just in case you’re not familiar with it, the steps of the scientific method go something like this:
- Ask a question
- Do some research
- Form a hypothesis
- Do an experiment with independent and dependent variables
- Analyze your data
- Draw a conclusion
It looks good, right? It certainly seems to produce what scientists say when they report their findings.
Why the scientific method is a problem
The main problem with the scientific method is that it’s a laundry list of steps that doesn’t actually describe what most scientists do. The actual processes of science are messy and unpredictable. The analysis depends upon what data is taken, but the hypothesis might shift over time as more data comes in. Sometimes the “experiment” is simply collecting observations instead of some sort of controlled procedure. The actual process of science is much less procedural and infinitely more flexible and robust.
“So what?” you might ask. “Most students won’t end up being scientists anyway, so this is better than nothing, right?”
I don’t think it is. The biggest issue I’ve seen is that the scientific method encourages some rather fundamental misconceptions. For example, many anti-evolutionists argue that the lack of “experimental evidence” is a strike against the theory of evolution. However, those same fundamental data collection methods are the foundation of many other sciences, like astronomy, physics, biology, psychology, and medicine. More insidiously, however, it fosters the perception that science is a “once and done” thing. The scientific method doesn’t recognize, much less emphasize, the cyclical nature of science. Instead it has a clear start point and a clear end point, and suggests that the practice of science does as well. I can just imagine that most people think that scientific activities end something like this:
Scientist two: “Time for a brewski! Later we’ll crack open the big book o’ questions and choose our next experiment.”
Scientist one: “True dat.”
No wonder so many people are confused, frustrated, and even angry when the scientific consensus changes. From their point of view, we did the experiments, so why didn’t we get it right the first time? Where did we fail to follow the recipe? What’s wrong with science that it can’t produce repeatable results?
Of course, most scientists realize that this process of continually checking and verifying previous knowledge is a feature, not a bug. The only way to eliminate historical and personal bias is to continually re-observe, re-check, re-test, and re-analyze. The importance of verification, however, is lost in the scientific method as written.
The Cycle of Scientific Thinking
I would not dream of suggesting that teachers ditch the scientific method without providing an alternate framework for teaching science. I found great success using what I call the “Cycle of Scientific Thinking”. Instead of a linear list, the cycle emphasizes the cyclical nature of scientific discovery.
To introduce these ideas to my students, I started with “Observation”, at the top of the diagram. We spent a lot of time talking about what was interesting — those “huh… I wonder why that happened” moments. As you can probably guess, this involved a lot of demonstrations and reflection. I didn’t explain much, however; instead, I asked the students to think about what questions came up from what they’d seen. What had they seen that sparked their curiosity?
As you can see, the arrow in the upper left is labeled “Questions”, and it leads to “Model/Explanation”. (I’ll get to “Hypothesis” in a second.) At this point we tried to explain what we’d seen based upon what we knew. If we couldn’t come up with an explanation, we took more observations until we could. As the students actively processed what they were seeing they began to come up with ideas about what they thought was happening. It was around this time that I introduced the idea of a scientific model. As it turns out students mostly think of models as small copies of big objects (for example, model cars, model buildings, etc). That’s why I added the word “hypothesis” to the drawing — to help them understand how a scientific model is simply a description of a bunch of observations. It’s similar to the hypothesis idea of the scientific method, but encompasses more of the potential uncertainty inherent in real scientific exploration.
From there I started asking them for the implications of their explanation. After all, they now potentially had answers for the questions they’d asked; what did those answers therefore mean? If the model was true, what else must be true? We talked about good predictions versus bad predictions, and what might be necessary to check our predictions. That got us into a discussion of testing and experimentation. They asked some really good questions, and we talked about situations in which we couldn’t necessarily control all (or any) of the variables. That brought us back around to observations, which lead us to new questions. Those questions lead us to refine and improve (or sometimes completely junk!) the models we’d developed. The updated models suggested new predictions, which encouraged more observations, which… After several cycles of this I asked how confident they were in their model. This lead us into a discussion of scientific theories and supporting evidence.
Hopefully you can see how this process better replicates the actual scientific process. In addition, it put the students in control of their learning. They had a chance to try to figure out the puzzle of where soil came from, or why Weneger suggested that land masses might have once been all connected. We talked about the evidence that supports our current understanding of the formation of the Earth, as well as recent evidence that suggests we might not have our model quite right yet. Everything we did followed this cycle, and I did my best to demonstrate science as a way of thinking (processing and creating knowledge) instead of a laundry list of facts (dry stuff to be acquired from a book).
It would be an understatement to suggest that the students loved it. One of my own weaknesses in teaching elementary is that I have not had any training in classroom management. Because I was inviting the students to become scientists and collaborate with me I had to cede some of my authority to them; that sometimes made things difficult. But it was never because the students were misbehaving; instead, it was always because they wanted to take one last measurement, or argue more fiercely with a “colleague” over the interpretation of a given experimental result. In other words, they were acting like scientists (for both good and ill) and sometimes it could be difficult to rein in some of the less desirable behavior.
If I were teaching this course again I’m fairly sure that I’d base the course on the cycle of scientific thinking again. In fact, from here on out I think I’ll restructure any college science courses I teach to emphasize these ideas as well. I think ALL science educators could improve general science literacy by ditching the scientific method, and adopting instead habits of scientific thinking. I’m not the only one who thinks this way, either. But I’m just one guy, and not a full-time K-12 educator at that. Making this switch might involve challenges that I can’t anticipate.
What’s your experience? I’d love to hear from other teachers, professors, and educational specialists — what has been your experience in teaching the scientific method and scientific thinking?