Reflection on the Professional Development Experience as a Science Teacher and Research Project Team Member
Author: Heather McPherson
As a high school teacher, I found the experience of working on the Chantier 7 project both rewarding and enlightening. When I teach, I am intuitively aware of students’ pre-conceptions in science. My awareness is the result of teaching for 26 years. Since working on the Chantier 7 project I have become more aware how prevalent these pre-conceptions are, and how difficult is to change students’ intuitive ideas so they become aligned with accepted scientific models and theories.
I worked as co-author and author on some of the lesson plans that are available on the web site. These lessons plans include diagnostic items to assess student’s pre-conceptions. The lesson plans then provide activities that address the preconceptions and help students develop an understanding of accepted scientific models and theories.
One of the lesson plans I worked on dealt with evolution. I was fully aware that students’ preconception of evolution favored the Lamarckian notion of evolution (use/disuse) rather than Darwin’s theory of natural selection. After writing the lesson plan, I piloted the lessons as written. I used the diagnostic items at the beginning of the lesson. I probed students’ understanding, I elicited higher level thinking. Then I did the activity on Darwin’s finches, where students analyzed how type of food available to finches favored specific beak shapes, that birds whose beak was best adapted to a specific food had a greater likelihood of: (1) having offspring; and (2), passing the trait to their offspring. Natural selection at work. I also went through a PowerPoint presentation, students took notes. We did further sessions of probing, eliciting, making sense of data. Finally, I assigned the last activity in the lesson plan. I decided to have students research any example of natural selection and then, using a PowerPoint presentation, explain their example to the class.
To my complete dismay, all but one group explained their example of natural selection using Lamarck’s notion of use/disuse. I truly believed that I had resolved the issue of this preconception over the two weeks we developed the lessons on evolution. When students were left to their own devices, they fell back to their conceptual preunderstanding of natural selection. However, having the class work together during the presentations did finally put the use/disuse theory of evolution to rest. In the formal evaluation extended answer question on natural selection, all students were able to explain both theories, and to articulate why natural selection was accepted, and why use/disuse was not.
It took more energy and time than I anticipated. Working with the Chantier 7 lessons provided me with a sharper focus on the challenges of altering those strongly held student preconceptions. I was not as obvious as I thought. In the end, however, mission accomplished.