LEAPS Paper, Fall 2003
Joe Summers
Introduction
This paper aims to address the question: “What have you learned about instruction and pedagogy in the Grade 8/9 Classroom that you think you could apply to teaching at the undergraduate level?” In doing this, I will be addressing three main issues: teaching using students’ prior knowledge, gender equity in the science classroom, and questioning using adequate wait-time.
Prior Knowledge
Teaching and learning science can be difficult and abstract due to its vast size. A college-preparatory curriculum includes chemistry, physics, math, biology, as well as plenty of other non-science subjects, which students are expected to absorb over the short period of four or five years. Some of these subjects have histories that go back millennia but, for the sake of brevity and breadth, most of the history, frustration, and curiosity behind the science are left out of textbooks and lectures. This occlusion can lead students to wonder “how” and “why” science has progressed and allow them to perceive scientists as an esoteric group whose discoveries were made spontaneously and in isolation of current events or societal needs. This perception is, of course, wrong; the progression of science has been slow and often painful with many missteps, pieced together from what we’ve known about the world at different points in time, and frequently in response to human needs. Science is deeply rooted in our prior knowledge of things, and since it strives to improve upon this knowledge, it must be presented in the context of what students already know and understand in order for the learning itself to be scientific.
This isn’t really news to anybody: it’s common sense and there are a number of peer-reviewed research papers to support the use of prior knowledge teaching techniques. One in particular (Hewson and Hewson, 1981) reports the findings of a group in South Africa concerning the effective use of prior knowledge to teach mass, volume, and density to high school students. These topics were also taught in the 8th grade LEAPS classes at SBJHS using techniques similar to those described in the paper. Three techniques relied upon both by LEAPS participants and the South African group, are identified by Hewson and Hewson as conceptual bridging, differentiation, and integration. With conceptual bridging, new concepts are introduced to students using familiar examples. This technique was used at SBJHS to introduce density, where examples of boats, hot-air balloons, and other floating objects were provided in order to relate the concept of density to what students already intuited. Once this foundation was established, misconceptions were clarified using differentiation and integration. Students were made to differentiate between the concepts of density and mass by seeing how the mass of an object alone is not responsible for whether it will sink or float in water. This idea was explained further by integrating it mathematically with previously taught concepts of mass and volume (density = mass/volume). The students’ mastery of density was finally tested by having them integrate their understanding of the density of simple materials to explain how a complicated structure made out of relatively dense materials (e.g. a metal boat) could float on water. This provided an effective link between a mastered understanding of density and the earlier, familiar examples of floating objects.
Variations on these techniques were used successfully throughout the first quarter of LEAPS, and it’s evident that prior knowledge is an effective teaching technique.
There are many subjects in undergraduate science and engineering education that are traditionally taught in a abstract way and either don’t attempt to use prior knowledge to relate material to the students, or make incorrect assumptions regarding the students’ prior knowledge. An example that immediately comes to mind in the field of electrical engineering is Electromagnetism. Electromagnetism is often taught as a two or three course sequence and covers everything from static electricity to the principles behind electric motors and the interaction of light with different types of material. Even though Electromagnetism is one of the most powerful and applicable subjects an electrical engineering student can learn, the mathematics needed to describe structures of general interest (e.g. high speed computer chips, human tissues) cannot be expressed using simple formulas. Consequently, modern applications of electromagnetics are avoided in class in favor of simple, often abstract, structures that can more easily be described mathematically. To further hinder things, the nature of the subject is intrinsically abstract and difficult to imagine; radio waves are invisible, as are the fields from magnets and static electricity (ironically, the only electromagnetic waves we can see, light, are so small that under most circumstances we don’t typically see them behaving as waves at all). All of these things significantly reduce the number of conceptual bridges that can be made for the student, not to mention problems with differentiation and integration.
This all begs the question: how can the Electromagnetics instructor use prior knowledge to enhance lectures and course content?
One option that has great appeal is the use of computer simulations as a supplement to traditional coursework. In recent years, as the speed of computers has increased, it has become possible to simulate and visualize Electromagnetics problems of both great complexity and current interest. As an added benefit, many of these algorithms can be derived directly and simply from the few fundamental equations that describe all electromagnetic behavior (aka Maxwell’s equations). This simplicity would allow students to easily create their own algorithms and conceptually integrate their computer code with the basic physics of the entire subject matter. Perhaps the most exciting aspect of using computers for teaching Electromagnetics is the capability to visualize the movement and nature of electromagnetic fields and waves. Visualization allows an entirely new dimension for understanding electromagnetic wave phenomena, which could bridged conceptually to more familiar observed wave behavior such as acoustic waves on guitar strings or waves in the ocean.
Gender Equity
Gender equity has been a subject of discussion during LEAPS meetings on a couple of occasions, and I will be addressing it here with respect to a study of the factors considered by women when choosing a career (Baker and Leary, 1995). This study is comprised of interviews with school girls of different ages (2nd grade, 5th, 8th, and 11th) that attempts to reveal why women may or may not decide to pursue a career in science. The results of the study support the view that basic science is often perceived by women to be an isolated subject that doesn’t directly relate to helping people or improving the world. It also claims that this perception of science is at odds with typical female values and career goals that center on making connections and developing relationships that create community. As a result, the study finds that many women don’t choose careers in science, and the few who do are often influenced by affective connections with science established early in life through role models such as family members
In addition to these general findings, the study also examines girls’ attitudes at different grade levels to see how their views of science change with age. Among those interviewed were girls in 8th grade, which is the same age as students in the SBJHS LEAPS classroom. Baker and Leary found that 8th grade girls are typically not intimidated by science, and often view themselves as being better at it than boys. Despite this, they show that girls still hold stereotypical views of scientists as being mostly male and socially isolated. As the material becomes more advanced in the 8th grade, science lectures tend to take on more of a lecture format with extensive note taking, resulting in less socialization during class time. The girls in the study found this social isolation unappealing.
My experience with the 8th grade LEAPS classes is consistent with many of the Baker’s and Leary’s findings. I can see no discernable difference in the quality of work or the amount of participation between the boy or girl students. In fact, as the study suggests, many of the girls are more confident and show more interest in the material than the boys. One notable difference between the LEAPS setting and the work shown in the study is the method in which the material is presented. In the LEAPS classroom, the class is regularly broken up into small groups (6-8 students) with a Fellow leading each group. The small group format is used for laboratory experiments, homework discussion, and review for test preparation. I’ve found that this format provides a more social setting than the lecture environment and encourages more participation from each of the students. In addition to leading the small group format, Fellows are responsible for presenting their university research to students and relating to them the relevance and impact that research has on society. These presentations help illustrate the role of a scientist, the relevance of scientific research, and ways that their research is connected with people. Based on the study by Baker and Leary, all of these things should generate interest in girls for science-related careers.
At the undergraduate level, several undergraduate engineering programs have restructured the first year’s curriculum by integrating math classes with engineering physics classes, and by adding design classes to get students working on engineering projects early on. One such program is the Engineering First program at Northwestern University, a school which has a percentage of female undergraduate students far above the national average (31% of undergrad engineers are female, compared to the national average of 20%) and almost a 90% retention rate (Northwestern University, 2001). Northwestern attributes much of this success in attracting women engineers to the relatively large number of existing female students and faculty. Regardless, the addition of freshman design classes that emphasize engineering problem solving within small teams offers many of the same advantages given by the Fellows and the small group setting in 8th grade LEAPS classrooms. Science and engineering applications are made accessible to students through hands-on engineering projects, and teamwork provides socialization and connectedness with peers.
Wait-Time
Asking students questions and encouraging students to ask their own questions in class is an effective way of keeping track of their progress during a discussion. Questions also monitor and reward attentiveness, and challenge students to investigate the material while it’s fresh in their minds. Even though questioning is a widely adopted technique at all levels of education, the degree to which it is productive depends largely on wait-time, or the amount of time a teacher waits for a student to answer a question. There is evidence to show that increased wait-time substantially improves the quality and frequency of student responses (Rowe, 1974).
The topic of wait-time was introduced to LEAPS Fellows during the summer training workshop, and I’ve seen it applied by LEAPS Teachers during lecture in the SBJHS classroom. Rowe’s study shows that a waiting period of 3-5 seconds is necessary to improve student participation, yet most teachers allow on average only about 1 second of wait-time. LEAPS Teachers, who have been trained as educators and are experienced at asking students questions, make a point of waiting an appropriate amount of time for students to respond. As a result, the amount of participation by students in the LEAPS classrooms during discussion is high and students become part of the lecture.
The need to allow adequate wait-time is also necessary at the college level, where Rowe notes that the average wait time given by professors is less than 2 seconds. For science and engineering careers in academia, most professorships require only some teaching experience, usually in the form of a teaching assistantship. Consequently, many professors may not understand the importance of allowing adequate wait-time, and effective communication between the students and professor during lecture isn’t established.
References
1. Hewson, Mariana G. and Hewson, Peter W, “Effect of Instruction Using Students’ Prior Knowledge and Conceptual Change Strategies on Science Learning,” Journal of Research in Science Teaching, Vol. 20, Num. 8, pp. 81-94, 1983.
2. Baker, Dale and Leary, Rosemary, “Letting Girls Speak Out about Science,” Journal of Research in Science Teaching, Vol. 32, Num. 1, pp. 3-28, 1995.
3. Web site, “Northwestern Holds 30th Annual Engineering Career Day for Girls,” http://www.northwestern.edu/univ-relations/media_relations/releases/feb2001/careerdayforgirls_text.html, viewed 1/7/2004.
4. Rowe, Mary B, “Wait-Time and Rewards as Instructional Variables, Their Influence on Language, Logic, and Fate Control: Part One – Wait-Time,” Journal of Research in Science Teaching, Vol. 11, Num. 2, pp. 81-94, 1974.