Observation and the Teaching of Science J a m e s H. Swinehati University of California, Davis, Davis, CA 95616 One eoal of science education is to nroduce a scientificallv literateupopulace capable of understanding the language and fundamental conceots of science. Science education. however, must also afford the ability to recall, locate, and assimilate factual information so that rational decisions can he made. It should provide the training and basis upon which individuals are challenged to solve more than routine tasks set for them by others. Rather, based on their own observations, individuals should be skilled in both the generation of their own questions and the process involved in finding solutions to problems. Teaching requires a balanced presentation oE ~
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1. Observations of phenomena related to the discipline. 2. Process skills, especially formulating questions fram ohserva-
tions. 3. Basic language of the discipline. 4.
Fundanwntal concepts.
b. Specific factuul infvrmatim 6. The It.gic hy which problems are solved
The ability to observe is thus an extremely important and necessary component in the evolution of anv discinline. The problems associated with teaching students to odserve are, however, not new (1-3). In an 1861 article discussine the study of the chemistry. Otto I.inne Erdmann indicnted'that his srudenrs were "strikinaly untrained in rhe use of their senses" (4). Accepting theabove premise, this article seeks to outline how such observational skills should be combined with specific concepts in the teaching of science a t all grade levels. UCDlNorthern Cailfornia Sclence Project The UCDINorthern California Science Project was initiated through a grant from the NSF toVictor Perkes, Department of Education, University of California, Davis, and was a program on current developments in biological and physical sciences as applied to secondary science programs. This project included over 30 secondary school teachers in northern California. Two of my colleagues, Wendell Porter and Eldridge Moore from the Departments of Physics and Geology, respectively, and I worked with the teachers in an effort to integrate observation skills with specific concepts of chemistry, physics, and earth science using an interdisciplinary approach. Many of the ideas we used evolved while we were members of a committee to evaluate the existing science program and to develop a model science program for the Davis Joint Unified School District. The sequential use of observations and questions formulated from these observations was the central teaching aporoach develooed bv this nroiect. I t must. however. be made hear that c o n k v e d e x p e i i m k s or demomtration$ that are put together to illustrate some "predetermined" concept or fact are not what is meant by observations. Rather, observations involve the examination of phenomena, which will provide a sensory basis for the student to ask probing questions. These auestions, as developed through student-teacher interchange, in turn, providethe basis for the development of the language, fundamental concepts, and factual information of the discipline. Students in groups of four to six were asked, for example, to observe the opening of a cooled bottle of a carbonated beverage and the pouring of its contents into
a glass. They were then challenged to formulate questions based on their observations. The instructor then used these questions as a vehicle to introduce course material. Observation as a Teachlng Vehlcie Can observation be used as the basis for teaching the laneuaee. - . fundamental conceots. . . and factual information of a discipline, and a t the same time can students use these observations to generate meaningful problems for solution? In order to use this approach i t is necessary to disregard the orderly divisions of a discipline found in textbooks and the ordered notes of most lecturers. It is important to realize that the ohservation-question formulation approach offers a realistic problem-solving pattern. In fact, i t is quite natural. Although most successful in an integrated curriculum that allows cross utilization of concents and total exnloration of a phenomenon, this approach can also be successfully incorporated into a sinele discinline. The instructor. however. must be willing to reference tkxt material rather than use thk rigid seauence i t would otherwise dictate. Addina- this degree - of freedom opens avenues to more thorough learning. Let us consider an example in more detail. Students are given a glass of water that contains several ice cubes. They are told to observe this solid-liquid water system for several minutes either individually or in groups of five or six. They should record the questions for which they would like answers on note paper. Typical questions include: Why does solid water float on liquid water? Why does the exterior of the glass container become covered with a layer of liquid water after some time? Why is there less solid water in the container as time passes? What causes the solid water to melt? Why is solid water normally opaque while liquid water is clear? Once the class is reconvened, the teacher should then use these questions to introduce and define key words such as solid, liauid, water, fluid, heat, temperature, melting, freezing, acid, base, phase, and heat capacity. ~ q u a t i o & representing the changes occurring in the solid-liquid water system can be written, and the students can be challenged with the fundamental concepts illustrated by the phenomena including: Structures of Molecules. Theories that predict the formula and
structure of water can be introduced including the three-dimensional relation o f ~ y g e nand hydrogens,and thcelecrron density. Hydrogen bonding resulting from acid-bnsa mterartrms and differences in the decree of hydroyrn ~. honding as related tosdidu and liquids can be dis&ssed as can the differences between the properties of water and other suhstances. Equilibrium. The halancing of heat loss and gained as a solid-liquid system moves toward equilibrium can be discussed. The amounts of heat required to cause phase changes and temperature changes for specificmasses of solid and liquid water can be calculated. The quantities needed in discussions of equilibrium coming fram the making and breaking of bonds (enthalpy) and order-disorder (entropy)can also be an integral part of the discussion. Dynamics. Areas for discussion might include an analysis of the factors affecting the rate at which a solid-liquid system moves toward equilibrium. Such factors include surface, diffusion, stirring, ete.; the relating of dynamics to equilibrium;and the general factors affecting kinetic processes. In an integrated physics, geology, and chemistry program such as that developed in the UCD/Northern California Volume 64
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Science Project, the following concepts and factual information can be expanded to include more interdisciplinary concepts such as: Buoyancy and Density. Areas for discussion include the physical laws governing a solid floating in a liquid, the meaning of density and specific gravity, the measurement of density, and the use of the concept of solids floating on liquids to discuss geological phenomena such as mountin ranges. Properties of Electromagnetic Radiation. Material could include the interaction of lieht with microcrvstalline materials versus " single crystals; refraction, diffraction, and reflection; colors in gemstones; and interference and reinforcement of electromagnetic radiation. Crystallirotion. Areas of interest could include properties at the solid-liquid interface,rates of crystal growth, formation of minerals from melts, and hydrothermal processes. FOCUS,Fact, and Logic
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In all interactions, it is important that the teacher continually separate the fundamental concepts from the language and factual information so that the fundamental concepts are clearlv defined for the student. Additionally, the teacher must ins& that the student visualize the structure and processes under discussion. This aspect of the process is most important for both formulating eoncepts and also evolving new problems to he resolved from observations. For example, a number of new problems can evolve in discussions related to the solid-liquid water system including: the effects of pollutants on the structure and properties of water, special types of ice, the development of life forms in a system in which the solid is more dense than the liquid, and the mechanism by which hydrogen or hydroxide ions are trans-
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ferred in hydrogen-bonding substances. Such topics can be used by students for special research projects. Often these projects can be related to finding solutions to the original questions posed about the system. If problems generated by others are to be solved by the student as part of the teaching program, it is important to emphasize both the logic skills required to solve these prohlems as well as the detailed mechanism required to solve a particular problem. Students should know that the first question they should pose when confronted with a problem is "What basic concept must he used in formulating the solution to the problem?" Then factual information is used for the details of the problem solution. Needless to say, most students fail to approach the solution of problems by this logic. Conclusion The basic thrust of the approach outlined above is to use the observations, which should be an integral part of all courses, to focus each student's attention and allow for the leisurely generation of questions concerning the object. These questions can he used to present the language, fundamental concepts, and factual information of a discipline. The teacher must clearly define the above components of a discipline so that the student uses the correct logic for solving problems. Literature Cited
fdmia: Berkeley, 1978. 4. ~
~E., Cibs-Geigy. ~ ~ Ltd.,Plarties t Division, ~ ~ Bssel, Switzerland, , personal
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