Knowledge and Learning#

Knowledge and Learning

Teaching and Learning Science

Teaching and learning science are both challenging endeavors. As instructors, we need to communicate complex, highly interconnected concepts that will serve as a foundation for all your future studies. We also want our students to demonstrate mastery of these ideas at a high level. As students, you need to learn a large new vocabulary, create mental models on which you can "hang" the new conceptual knowledge, and demonstrate that you can actually use this new knowledge. The process challenges both the instructor and the student. Although the process involves hard work, it can also be incredibly rewarding. There is nothing more satisfying for an instructor than those “Aha!” moments when a student suddenly understands an important concept.

In BIS2A we face some interesting teaching and learning challenges. One key challenge is that we discuss physical things and ideas that exist or happen on time and/or size scales that are not familiar to most students. What does this mean? Consider the following example:

Example: Some challenges associated with creating mental models

An instructor teaching wildlife biology may want to talk about concepts in evolution by using bird beaks as a starting point for discussion. In this case, the instructor does not need to spend time creating mental pictures of different shaped bird beaks (or at the very least only needs to show one image); most students will readily draw on their past knowledge and everyday lives to create mental pictures of duck, eagle, or wood pecker beaks and infer the different functional reasons why Nature might have selected different shapes. As a consequence, the students will not need to expend any mental effort imagining what the beaks look like and can instead focus all of their energies on the core evolutionary lesson.

More colloquially: If you are asked to think about something new that is closely related to something you already know well, it is not too difficult to focus on the new material.

By contrast, in BIS2A we ask students to think about and discuss things that happen on the atomic, molecular and cellular scales and at rates that span microseconds to millennia. Most students, we will guess, have not lived life on the micro to nanometer scale. Yet, this length scale is where most of the events common to all biological systems takes place. Beginning students, who have not thought much about how things happen at the molecular scale, lack of mental models upon which to add new information. This starting point places a burden on both the student and the instructors to create and reinforce NEW mental models for many of the things we talk about in class. For instance, to really talk about how proteins function, we first need to develop a common set of models and vocabulary for representing molecules at the atomic and molecular levels. Not only do these models need to find ways of representing the molecule’s structure, but the models must also contain abstract ideas about the chemical properties of molecules and how these molecules interact. Therefore, students in BIS2A need to put some effort into constructing mental models of what proteins "look" like and how they behave at the molecular scale. Since the entire course centers around biomolecules and processes that happen at a microscopic scale, a similar argument can be made for nearly every topic in the class.

Note: Possible Discussion

How do you interpret the term mental model and why do you think that it is important for learning?

Some of the in-class and study guide exercises are designed to help with meet this challenge; most students have found them very useful. However, some students are more accustomed to studying for exams by memorizing information rather than understanding it. (It's not their fault; that's what they were asked to do in the past). As a result, if the problems are approached with the "memorize-at-all-costs" attitude some of the BIS2A exercises may initially seem pointless. For instance, why are your instructors asking you to repeatedly draw some of the concepts described in class? What multiple-choice question could that exercise possibly prepare you for? While it is true that some of your instructors won't ask you to draw complicated figures on an exam, these drawing exercises are not trying to prepare students for one specific question. Rather the instructor is trying to encourage you to begin creating a mental model for yourself and to practice using it. The act of drawing can also serves as a "self test." When you force yourself to write something down or to create a picture describing a process on paper, you will be able to independently assess how strong your conceptual grasp of a topic really is by seeing how easy or hard it was to put your mental image of something onto paper. If it is hard for you to draw a core concept or process from class WITHOUT EXTERNAL ASSISTANCE, it is likely that you need more practice. If it is easy, you are ready to add new information to your model. Throughout the course, you will continue to add new information to your mental model or to use the concept represented in your mental model in a new context. Keep your drawings - or other self-testing mechanisms - current. Don't fall behind.

Incidentally, the presentation of a course concept on an exam in a context that the student has never seen before is NOT an evil plot by the instructor. Rather it is a way for the instructor and student to assess whether the concept has been learned and whether that knowledge can be used/transferred by the student outside of the specific example given in class or in the reading. Asking the student to repeat the latter would represent an exercise in memorization and would not be an assessment of valuable learning and independent thinking or a representation of what happens in real life.

IMPORTANT: The idea that students in BIS2A will be tested on their ability to USE concepts in specific contexts that they haven't seen before is critical to understand! Take special heed of this knowledge. Developing usable conceptual knowledge takes more discipline and work than memorizing. The quarter also moves VERY fast and concepts are layered one on top of the other. If you get too far behind, it is very, very difficult to make up for lost time two or three days before an exam. Be as disciplined as you can and keep up with course materials.

So, some concepts are hard to teach and to understand. What are we to do? Something instructors and students both do is to use various communication tricks to simplify or make abstract ideas more relatable. We use tools like analogies or simplified models (more on the importance of these shortly) to describe complex ideas. Making things more relatable can take various forms. Instructors might try to use various simlies or metaphors to take advantage of mental pictures or conceptual models that students already have (drawn from everyday life) to explain something new. For instance, the thing X that you don't understand works a little like thing Y that you do understand. Sometimes, this helps ground a discussion. Another thing you might catch an instructor or student doing is anthropomorphizing the behaviors of physical things that are unfamiliar. For example we might say molecule A “wants" to interact with molecule B to simplify the more correct but more complex description of the chemical energetics involved in the interaction between molecules A and B. Anthropomorphisms can be useful because, like similes and metaphors, they attempt to link the creation of new ideas and mental models to concepts that already exist in the student's brain.

While these tools can be great and effective they nevertheless need to be used carefully - by both the instructor and the student. The main risk associated with these simplifying tools is that they can create conceptual connections that shouldn't exist, that lead to unintended misconceptions, or that makes it more difficult to connect a new concept. So while these tools are valid, we - students and instructors - also need to be vigilant about understanding the limits these tools have in our ability to learn new ideas. If these pedagogical tools are useful but their use also carries risk, how do we proceed?

The remedy has two parts:

1. Recognize when one of these "simplifying" tools is being used and

2. Try to determine where the specific analogy, metaphor etc. works and where it fails conceptually.

The second instruction is the most difficult and may prove challenging for learners, particularly when they are first exposed to a new concept. However, the act of simply thinking about the potential problems associated with an analogy or model is an important metacognitive exercise that will help students learn. In BIS2A your instructors will occasionally expect you to explicitly recognize the use of these pedagogical tools and to explain the trade-offs associated with their use. Your instructors will also help you with this by explicitly pointing out examples or prodding you to recognize a potential issue.

Note: Possible Discussion

Can you give an example from your previous classes where an instructor has used an anthropomorphism to describe a nonhuman thing? What were/are the trade-offs of the description (i.e. why did the description work and what were its limitations)?

Using vocabulary

It is also worth noting another problematic issue that can needlessly confound students just starting out in a discipline - the use of vocabulary terms that potentially have multiple definitions and/or the incorrect use of vocabulary terms that have strict definitions. While this is not a problem unique to biology, it is nevertheless important to recognize that it occurs. We can draw from real-life examples to get a better sense of this issue. For instance, when we say something like "I drove to the store", a couple of things are reasonably expected to be immediately understood. We don't need to say "I sat in and controlled a four-wheeled, enclosed platform, that is powered by the combustion of fossil fuel to a building that collects goods I want to obtain and can do so by exchanging fungible currency for said goods" to convey the core of our message. The downside to using the terms "drove" and "store" is that we have potentially lost important details about what really happened. Perhaps the car is battery powered and that is important to understanding some detail of the story that follows (particularly if that part of the story involves calling a tow truck driver to pick you up after the car has broken down). Perhaps knowing the specific store is important for understanding context. Sometimes those details don't matter, but sometimes if they aren’t known it can lead to confusion. Using vocabulary correctly and being careful about word choice is important. Knowing when to simplify and when to give extra detail is also key.

Aside:

In the laboratory, undergraduate students in biology will often report back to their mentors that "my experiment worked" without sharing important details of what it means to have "worked", what the evidence is, how strong the evidence is, or what the basis is for their judgment - all details that are critical to understanding exactly what happened. If and/or when you start working in a research lab do yourself and your advisor the favor of describing IN DETAIL what you were trying to accomplish (don't assume they'll remember the details), how you decided to accomplish your goal (experimental design), what the exact results were (showing properly labeled data is advised), and providing your interpretation. If you want to end your description by saying "therefore, it worked!" that's also great.

Note: Possible Discussion

Can you think of an example where the imprecise or incorrect use of vocabulary caused needless confusion in real life? Describe the example and discuss how the confusion could have been avoided.