EXPERIENTIAL SCIENCE: AN "EXPERIENCE FIRST" APPROACH TO TEACHING AND LEARNING SCIENCE

Shawn M. Bullock

This action research report was prepared as part of the course requirements for Queen’s University’s Bachelor of Education program during the 1997-1998 academic year. Teacher candidates were introduced to the concept of action research in their August orientation session. Midway through the ensuing four-month practicum, teacher candidates returned for two weeks to the Faculty of Education, where they were urged to reflect on their early experiences learning to teach. At this point, teacher candidates were required to discuss their action research topics with their Professional Practice course professors. Since there were a large number of action research reports (mine included) that dealt with the nature of the subject curriculum, many teacher candidates discussed their projects with Curriculum professors. The final product was shared with colleagues at Queen’s in January, 1998.

A combination of the innovative atmosphere of my school’s science department and discussions that I had with my curriculum professor led me to explore alternative science pedagogy. For my action research I selected the question, "Would using an ‘experience first’ approach to teaching science improve the quality of my science teaching, and hence the quality of learning in my classroom?"

Like most teacher candidates, I relied heavily on the comments and suggestions of my associate teachers as I developed my "experience first" approach to teaching science. To record my progress, I kept a daily journal. After the two week on-campus period, I began e-mailing my journal to my physics curriculum professor for him to comment on. This proved to be an invaluable resource to supplement an extremely supportive associate teacher (see Russell & Bullock, 1999). As I implemented an experience-laden pedagogy, I was constantly soliciting student reactions to gauge my success. Lab reports, assignments and tests that were prepared with experience-laden pedagogy all provided useful clues to how students were faring with the new approach. Finally, I conducted a survey at the end of my practicum to find out how students felt about an experience-first approach.

A Classical Approach

Traditional science teaching can be broken down into two components: theory and experiments. The traditional approach emphasizes theory over experiments. The majority of the time in a traditional science classroom is spent on theory, and experiments are used to supplement the theory previously presented in class.

For example, the Grade 12 advanced physics curriculum includes a unit on gravity. By the end of the unit, students are to understand the physical meaning of gravity through Newton’s Law of Universal Gravitation, and to calculate the force of gravity between various objects. The classical approach would be to introduce the idea of what gravity is, and perhaps how it affects our daily lives. The next logical step would be to discuss Newton’s Law of Universal Gravitation, showing that one can determine a gravitational constant (abbreviated "g") that governs the rate of acceleration due to gravity near any planet. You would then mathematically derive that the rate of acceleration due to gravity near Earth is approximately 9.80 m/s2. Time permitting, students could revisit their kinematics equations and conduct the simple experiment of dropping a ball down a stairwell, timing the fall, and rearranging an equation to determine that g = 9.80 m/s2. Practice problems would follow.

Most students have been learning by this method for many years. Indeed, it was enough to prompt me and many others to study science at the post-secondary level. A range of credible arguments support teaching science in this fashion, chief among them being that doing an experiment after the theory is presented allows students to apply the knowledge they have gained in the classroom. Despite the success of this theory-laden pedagogy for those bound for university, I have come to believe that science courses should shift their focus to an approach that has more emphasis on experiments that precede theory.

The Need for Change

Many experiments conducted at the secondary level cannot be considered true learning exercises because of the confusion surrounding the typical high school experiment. Virtually every science teacher on the planet has heard a student utter the phrase, "So what exactly are we supposed to do?" during a experiment, even though each student was given a handout that was prepared with the express purpose of avoiding that question. Usually, the students who understand the lab go through the motions of the experiment to get a good mark. Their less fortunate peers follow along and quite often will copy data outright. Since the students already know what the lab is supposed to illustrate, they can alter data to make their calculations have a ridiculously small margin of error.

I would argue that this approach creates a false image of the scientific method, which many see as the core of any science course. The scientific method is quite simply a philosophy of wondering about the universe: an experiment is designed and carried out to test predictions based on everyday observations. The traditional method of teaching science outlined above robs students of the scientific method. They already know the outcomes of experiments before they do them, so labs are reduced to little more than developing the motor skills required to get "good" data. I am concerned that the theory-laden model of scientific teaching robs students of the "fun" of science.

Experience First

On my practicum, I took an "Experience First" approach to teaching science. I defined my "Experience First" approach to science as having two components, which I discuss in turn. The first part of the "Experience First" philosophy shapes a teacher’s approach to the high school laboratory. When a new unit that will have an associated lab is introduced, it is important not to give away everything there is to know about the topic. The first lesson in any unit should be an introduction that gets students excited about the topic. Although it is not always feasible, the end goal should always be to make the students wonder how they have lived to this point in their lives without knowing everything there is to know about that topic. Allow the students to ask as many questions as possible and debate it amongst themselves. In junior science classes, I often had students write down the questions that they wanted answered by the end of the unit. This technique gives the students some ownership of the unit by convincing them that it is something useful and not just something on the curriculum. I started all units off that way, not just the lab-intensive ones.

The introduction should, if possible, be immediately followed by an experiment that students perform. Conclusions that were not already taught to the students can hopefully be drawn. After the experiment has been performed, the students should be drawn back together, and the conclusions from the experiment should be developed. It is important to let the students talk about what they have learned. The formal lab write-up would then be handed in at the following class. The theory that would usually have preceded the experiment would then be consolidated in the ensuing classes.

The second portion of the "Experience First" approach to science teaching involves a technique referred to in the Australian PEEL project (see Baird & Mitchell, 1986, and Baird & Northfield, 1992) as "P.O.E."—Predict, Observe, Explain. P.O.E.s are designed to engage the students in science, and I used them in portions of the curriculum where experiments were not practical. P.O.E. provides a powerful methodology for conducting demonstrations in the science classroom (White & Gunstone, 1992, pp. 44-64). The teacher sets the stage for the demonstration by explaining the situation. The teacher then asks students to predict what is going to happen (or not happen), making sure not to give criticism or validation. After collecting a range of predictions, students are invited to offer possible explanations supporting the predictions. The teacher then conducts the demonstration and students record what they observe. Finally, the class and teacher work together to explain what they observed, with special reference to earlier explanations. Creating an environment that welcomes a range of predictions and explanations before the observation usually sets the stage beautifully for focusing in on the correct explanation after the observation.

This two-tiered approach to Experiential Science is based on a combination of discussions that I had with my associate teacher and my physics curriculum professor, on reports from the PEEL project and on my own ideas about science teaching.

The "Experience First" Pedagogy

I started implementing my "Experience First" pedagogy by asking my students a range of questions based on everyday experience. I wanted to demystify physics to some extent, by pointing out that physics is merely a way of empirically describing everyday actions.

The P.O.E. model was more versatile than I had originally imagined. Initially, I saw P.O.E.s as alternatives to experiments. But the more I used them, the more I found that they were useful in other parts of a class. I started using them as hooks for the beginnings of my classes: I would have something set up at the front of the room, and pique the students’ interest as I walked into the room. P.O.E.s can also be used in the middle of a lesson to see if students really understand what they have been taught. A list of some of the P.O.E.s I used in my classroom follows:

• The students walked into class to find me standing on a skateboard. I had some of them push me with varying amounts of force to see the relationship between force, mass, and acceleration. (Newton’s Second Law)
• I glued a film canister on top of a hot wheels car, filled the canister with vinegar, and injected baking soda into the canister. An explosion caused the top to be blown off, and the car to be thrown forward (Newton’s Third Law)
• I placed three cigarettes in a jar of water during a Grade 9 class on disease, and let the tar diffuse out.
• I dropped objects of different weights and shapes to investigate the laws of gravitation.

The so-called "experiential labs" took on a variety of forms. The one constant, however, was the fact that I never gave out a lab instruction sheet. I had several reasons for this, chief among them being that students never seem to read them. I give the instructions orally, being sure to emphasize key points. I encourage the students to rewrite the instructions in their own words so that the instructions make sense to them when it comes time to do the experiment. We discuss the experiment the day after it is complete, to tie together the conclusions. I try to let the students do as much of the talking as possible and to debate why different groups found different results (a situation that invariably occurs). The lab is due to hand in at the following class.

The true test of Experiential Science came, when I asked students in my Grade 12 physics class to design their own experiments to determine the gravitational constant for Earth. This was towards the end of my fall practicum, so students were more comfortable with the new classroom procedures. The "experiential lab" on gravity was spread over four classes. The following is a day-by-day account of those classes.

Day 1 The physical definition of force was not new to the students, because they had just completed a unit on Newton’s three laws of motion. I began by asking the students to name the kind of force they knew the most about (aside from the one that Obi-Wan showed Luke). It did not take long for the idea of gravity to come up. I then jumped straight into a P.O.E. that centred on two pieces of paper. I showed the class two pieces of standard notebook paper and asked what would happen if I dropped the two horizontally-oriented pieces of paper at the same time from the same height. The students predicted that the papers would fall due to gravity, hitting the ground at the same time because they were the same mass. I then performed the experiment, and the students’ predictions were confirmed. I then crumpled up one of the pieces of paper and asked if I had changed the mass of the paper. The class was confident that changing the shape of the paper did not alter its mass. I then asked students to predict what would happen if the crumpled paper and the regular paper were dropped at the same time from the same height. Some students predicted that the results would be the same because the mass of the paper had not changed. Other students predicted that the crumpled piece of paper would fall first because it would encounter less air resistance. I dropped the two pieces of paper, and students observed that the crumpled piece of paper fell to the ground first. The next step was to get the class to explain what these results implied about the nature of gravity. I led the class to the conclusion that the results of the demonstration implied that the rate of acceleration due to gravity was independent of the mass. The students left the class with the idea that all objects experience the same acceleration due to gravity near the surface of the Earth.

Day 2 I began by asking the students about the conclusion reached in our previous class. Not many students accepted that all objects experience the same acceleration due to gravity near the Earth’s surface. They told me that it only "made sense" that the more massive an object was, the faster it would accelerate towards the Earth. The class soon became eager to prove the theory wrong.

I led them through the design of four experiments intended to find out if the acceleration due to gravity near the Earth’s surface is constant. Although I had a few experiments in mind, I let the students come up with the methods as a class. The experiments that we developed were as follows:

1. Drop Zone: A rubber stopper is dropped from the top of a stairwell (a measure height), and the time of descent is measured using a stopwatch. Using basic kinematics equations, the acceleration (due to gravity) that the rubber stopper experiences can be determined (since distance and time are known). There is an inherent timing error in this experiment because the speed of light is much greater that the speed of sound. A small time differential is introduced because the student at the top who yells "GO!" to start the experiment is relying on the speed of light to observe the time at which the object is released, whereas the person who starts the stopwatch at the bottom level is relying on the speed of sound to hear the word "GO!"
2. Drop Zone-The Sequel: This experiment is identical to the first one, except that a ticker timer is used to get a more accurate reading of the time. The students had used a ticker timer in an earlier lab to investigate uniform motion.
3. Pendulum: I had to give the students the formula relating period and acceleration of a pendulum, because this topic is not dealt with until OAC Physics. The students were able to time how many periods a pendulum swings in a certain amount of time. It is possible to determine the acceleration due to gravity if the length of the pendulum and the period of its swing are known.
4. Photogate: This experiment allowed the students to use real time sensing software available at the high school. A photogate was hooked up to a CHAMP II interface box, and a picket fence was dropped through the photogate (a picket fence is a rectangular piece of clear plastic with a series of opaque and transparent stripes). The picket fence alternated between interrupting the infrared beam and allowing the beam to pass unhindered, so the computer was able to construct a velocity-time graph of the fall. The students knew that the slope of the velocity-time graph would give them the acceleration due to gravity.

With the exception of the pendulum, all the experiments were based on work done earlier in the year. The students were given the remainder of day two to work on these experiments.

Day 3 Based on student demand, this entire class was devoted to completing the experiments.

Day 4 This final day involved discussing the results and wrapping things up. The labs had shown the students that all objects near the Earth’s surface experience an acceleration due to gravity of approximately 9.80 m/s2. I asked the students to write their results as formal lab reports to be handed in the following day.

After the gravity labs were handed in, I developed Newton’s Law of Universal Gravitation for the students, in the hope that the concept of a gravitational constant for any large body would not be nearly as esoteric for them. The practice problems that I assigned were completed by the students with relative ease, and I heard students talking about what they learned in the labs as a basis for answering a mathematical problem. I observed that while many students understood the concept of gravitational acceleration after completing the lab, some did not understand it fully until they had completed the problems. I was confident at the end of the unit that the students understood the nature of gravity in a Grade 12 context.

Conclusions

As with any short-term study, it is difficult to give a definitive answer regarding the success of Experiential Science. There were many indicators, however, that the underlying philosophy of the methods I employed bears further investigation. P.O.E.s were highly successful in both the Grade 9 science class and the Grade 12 advanced physics class. I found that it was important to regard the P.O.E. as a performance. The more the students felt like they were watching a "show," the more likely they were to become as enthusiastic about the concept as I was. I also found that P.O.E.s were invaluable for "hooking" the class into studying the topic. Having apparatus set up at the front of the room at the beginning of class instantly set the stage for a P.O.E., and quite often the students would try to figure out what the apparatus was supposed to demonstrate before I began the class.

The other highly successful aspect of Experiential Science was the question-and-answer dialog I managed to establish. This dialog differed from the Socratic questioning teachers traditionally use in that the students had more ownership over the discussion because I encouraged students to answer their classmates’ questions. The Grade 9 science class seemed particularly suited to this type of learning. I found that the Grade 9 class invariably asked questions based on their own experiences, and at the outset I tried to answer them as best I could on the spot. I decided early on to turn their questions into an exercise for the students by asking them to set up a question-and-answer section in their notebooks. Periodically, I would assign a science-related question that they had to research. These questions included some of my own design and some that came up in class. Over the course of the term, the students investigated the minimum size of mirror they would need to view their whole body, the phenomenon of Northern Lights, the question of why the sky is blue, and even the nature of cancer. I found the question-and-answer sections to be useful and motivating for the students, often turning into a competition. More than a few times I had to cut short some answers that sounded like Ph.D. dissertations. To give added incentive for recording all of the questions and answers, selected questions from the question-and-answer section of their notebooks were included in each test.

While I am confident that the placement of the labs in the experiential science model is accurate, I believe that more work must be done to make experiments into the learning exercises they should be. I found that students put more time into having their lab write-up in the proper form than into drawing meaningful conclusions from their experiments. I managed to circumvent this to some degree by taking up the experiments in class and leading the students to correct conclusions, but I would prefer seeing the students draw their own conclusions.

Evidence

One of the best methods of drawing a conclusion from any study is to ask for reactions from those who participated. To that end, I surveyed students in my Grade 12 physics classes. I asked students if they preferred doing experiments before or after discussing the theory in class (i.e., did they prefer the "classical" approach to lab work or the experiential approach?). I also asked the students to comment on how they would like experiments conducted, and how they liked the P.O.E. procedure.

To my surprise, the responses to the survey varied widely. Approximately 60% of the students thought that it was better to have the experiment after discussing the theory in class. After all, this is the approach they have experienced for many years. These students felt that "you can base what you learn in class on how you do your lab." Conversely, those students who preferred the Experiential Science approach felt that doing the lab first helped them visualize the theory. There are clearly more questions that need to be answered surrounding the nature of Experiential Science and its impact on student learning. The students were unanimously in favour of P.O.E.s, and I was pleased to learn that many students found them "fun," "interesting," and "challenging."

Based on the scope of this action research report, I believe that the methodology surrounding Experiential Science bears further investigation. I found that P.O.E.s and questions based on experience were highly motivating and enjoyable for the students. They certainly made my job as teacher more interesting. I look forward to beginning my full-time teaching career in September of 2000, when I will begin the school year with a major focus on the goal of having students experience science.

Reference List

Baird, J. R. and Mitchell, I. J. (Eds) (1986). Improving the Quality of Teaching and Learning, Melbourne, Monash University Printery.

Baird, J. R. and Northfield, J. R. (Eds) (1992). Learning from the PEEL Experience, Melbourne, Monash University Printery.

Russell, T. and Bullock, S. (1999). Discovering our Professional Knowledge as Teachers: Critical Dialogues about Learning from Experience, in J. Loughran (Ed), Researching Teaching, London, Falmer Press.

White, R. and Gunstone, R. (1992). Probing Understanding, London, Falmer Press.

Bibiographical Note:

Shawn Bullock,
Final year in University of Waterloo Co-op Science Teaching.

Academic Background:

• Candidate for Honours Bachelor of Science (Co-op) in Physics from University of Waterloo, May 2000
• Candidate for Bachelor of Education, Queen's University, May 2000

Areas of Current Interest:

• The role of experience in student and teacher learning
• The importance of being a reflective practitioner
• Encouraging students to develop Good Learning Behaviours

E-Mail Address: shawnatqueens@gmail.com