Conceptual Challenges
Heather’s Challenges
In “A Private Universe” (1987), Heather presents misconceptions about what causes the seasons, the most interesting being the earth having a curly-q orbit. She believes, like many of the Harvard grads, that the seasons are a result of the elliptical orbit of the earth around the sun and the distance from the sun during the orbit. She posits that light can bounce and come around the earth even after the teaching which involved viewing a model of the solar system.
Challenge Topic – Mass and Gravity
The challenge topic I chose to investigate was misconceptions about mass and gravity. Students often have difficulty with the concept of objects with different mass accelerating at the same rate when dropped (being under the sole influence of gravity). Greater mass objects only fall faster than lower mass objects when there is air resistance. Acceleration of an object is directly proportional to force and inversely proportional to mass (F/m).
According to the study by Gonen (2008) in Turkey, science and physics pre-service teachers “had serious misconceptions about inertia, gravity, gravitational acceleration, gravitational force and weight concepts” (pg. 70). There is a concern that they will pass on their inaccurate explanations to students, further supporting misconceptions. Gonen (2008) discovered that people are resistant to changing their inaccurate understanding of science concepts which our class readings also support (Confrey, 1990; Driver, Guesne & Tiberghien, 1985; Posner, Strike, Hewson & Gertzog, 1982). In this study, 267 students in two groups, Science and Physics teachers, were given three tests: a physics test related to mass and weight concepts, the Logical Thinking Ability Test, and an Attitude Scale towards physics lessons. The physics teachers had better attitudes and higher achievement scores than the general science teachers, but the general science teachers still had a positive attitude towards physics; 84% had sound knowledge on the subject in comparison to 26% respectively; partial understanding was 10% and 59%; partial understanding with specific misconception, specific misconception, or no understanding at all was 6% and 15% (pg. 74). Gonen (2008) concludes that science teachers have difficulties describing and using mass and gravity terms. She postulates that this problem may stem from the explanation of their teachers and textbooks with unclear explanations; however, it’s also observed that a person’s understanding evolves as they mature and become capable of abstract thinking, and the study subjects have different training levels (pg. 79). It is possible for misconceptions at every level of education because “it is easy to draw incorrect outcomes from incomplete models” (pg. 79). This example with adult subjects who are considered as having competent academic ability demonstrates that people have personal ideas about the world and need to undergo a process of remediation (Driver et al., 1985) to assimilate or accommodate new information (Posner et al., 1982). Gonen (2008) concurs that misconceptions are a natural and unavoidable part of learning.
Digital Technology and Instructional Activities
One instructional activity that would assist understanding of mass and gravity would be to create a vacuum and test (example) dropping objects with varying mass to see that the concept always holds true. I remember doing this in my high school physics class and it was memorable and effective. Technology has the capability of demonstrating through software modeling, but I think that the physical testing will be more likely to result in the student making a “conceptual exchange” (Gonen, 2008, pg. 72). A software simulation could be helpful in introducing and visualizing the concept, then move to the physical testing. I found this explanation and this Educational Portal video helpful. It’s great how the quiz question points back to the location in the video that teaches the initial concept.
References:
Confrey, J. (1990). A review of the research on student conceptions in mathematics, science, and programming. Review of research in education, 16, pp. 3-56. Retrieved January 8, 2014, from http://ezproxy.library.ubc.ca/login?url=http://www.jstor.org/stable/1167350.
Driver, R., Guesne, E., & Tiberghien, A. (1985). Children’s ideas and the learning of science. Children’s ideas in science. Retrieved January 8, 2014, from http://staff.science.uva.nl/~joling/vakdidactiek/documenten/driver.pdf.
Gonen, S. (2008). A Study on Student Teachers’ Misconceptions and Scientifically Acceptable Conceptions About Mass and Gravity. J. Sci. Educ. Technol, 17, pp. 70-80. doi: 10.1007/s10956-007-9083-1. Retrieved January 9, 2014, from Academic Search Complete, UBC Library.
Posner, G. J., Strike, K. A., Hewson, P. W. & Gertzog, W. A. (1982). Accommodation of a scientific conception: Toward a theory of conceptual change. Sci. Ed., 66, pp. 211–227. doi: 10.1002/sce.373066020.
Smithsonian Center for Astrophysics. (1987). A Private Universe [film]. Retrieved January 7, 2014, from http://learner.org/resources/series28.html?pop=yes&pid=9.
Media Credit:
<wallpapersWIDE. (2014). Blue Planet. Retrieved January 6, 2014, from http://wallpaperswide.com/blue_planet_3-wallpapers.html.
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Responses
Hi Kimberly!
I like your post. I teach adults Physics and gravity is a very confusing topic indeed! Do you find that there is often misconceptions around velocity and acceleration? In my practice, students really grapple with the example of an object being thrown upwards. Understanding that once the object leaves the hand travelling upwards (or downwards for that matter), acceleration is constantly downwards is a struggle I watch most students go through.
I also agree that experimentation is key to trying to “throw a wrench into the gears” and challenge those misconceptions. The design of the experiment is crucial as it should confront some of those misconceptions commonly held and cause students to pause and question.
In the “vacuum experiment”, did you manage to confront the idea of distance and accelerating objects due to gravity? Again, students may hold the idea that heavier objects accelerate faster and may never agree because the experiment occurs over short distances???
Cheers,
Mel Burgess (good to see you again!)
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Dr. Khan:
Thank you Kimberley for unpacking the research you read in sufficient and concise detail. It helps with understanding what was studied, measured, and how, in addition to reporting outcomes on research. In terms of mass and gravity, as well as air resistance, the scope of the rule about objects falling at the same rate applies under certain conditions as you note. Given this, how might we work with students who have varied personal experiences or note lab results to the contrary? The Gonen article contributes another important facet to our discussion (underscored as well by others) and that is that teachers may be a source of alternative conceptions– Samia
Hi Mel,
Thanks for your response. I do not have the experience of teaching velocity and acceleration, but it would not surprise me at all if that was an issue. Primarily, I have taught English, but I now also teach other subjects including Math (in my Alt Ed program) — so far the Sciences have been ‘farmed out’ to a Science teacher. I remember my own experiences in taking Physics in grade ten; although we did numerous questions, the concepts didn’t really stay with me over time except in a superficial way (with misconceptions…or fumblings in trying to explain it).
I had not thought about the ‘over distance’ idea which wouldn’t be clear with the vacuum experiment. The only other idea I have would be to use a video that explains/demonstrates the concept over large distances.
Nice to see you again too! Always great dialogue. 🙂
Response to Dr. Khan:
The vacuum experiment with a feather and a heavier object illustrates the point of gravitational pull acting the same on two objects with varying mass, but there is still the potential for students to think that with a larger fall the ‘law’ would not hold true, and this could be supported by personal experience with dropping objects that have different weights (and mass). They might have even experienced what seem to be counter-examples repeatedly, so there would be a need to repeat the experiment with different object and different heights if that’s possible. There needs to be an effort to triangulate results. Another method that would support the law of gravity would be experiments with air resistance. I have just learned that there is software that models fluid (air) dynamics to demonstrate how air moves in a variety of situations, like in a wind tunnel. A third support could be an experiment with objects of different masses dropped attached to parachutes. Instead of showing that there’s no air resistance in a vacuum, show that there is air resistance in our natural environment that does affect movement according to mass. Using other methods to support the law can help to dispell the misconceptions that still hold after only seeing one controlled scientific example.