AAAS Commission on Science Education - American Chemical Society

AAAS in the spring of 1962. The Commission has accepted the responsibility for stimulating improvement in science education at all academic levels. A ...
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Arfhur H. Livermore

Deputy Director of Education American Association for the Advancement of Science Washington, D.C.

AAAS Commission on Science Education Elementary science p r o g r a m

T h e AAAS Commission on Science ~ d u cation was established by the board of directors of AAAS in the spring of 1962. The Commission has accepted the responsibility for stimulating improvement in science education at all academic levels. A major activity of the Commission since it was established has been the preparation and evaluation of science materials for the early grades. These materials are a series of exercises designed to improve the child's skills in using the processes of science. They are published in trial edition under the title Science-A Process Approach. Exercises for kindergarten through grade three develop the child's skills in these processes: observing, classifying, measuring, communicating, recognizing space/time relations, recognizing and using number relations, inferring, and predicting. I n each successive exercise in a sequence the child is expected to increase his skills in using that process. Observing, for example, starts with simple observations using various senses, and progresses to observations of animal motion, bacterial growth, and plant growth. Recognizing space/tiie relations starts in kiudergarten with simple activities designed to develop skill in recognizing two- and three-dimensional geometric shapes and in recognizing these shapes, or close approximations of them, in animate and inanimate objects. The sequence includes exercises on direction, time, straight and curved lines and surfaces, rate of change of position, and, finally, relative position and motion. The titles of the exercises in the measuring sequence illustrate how a process is treated as a continuing thread. Kindeqp&n. Beginning Memurement-Comparing Lengths; Linear Measurement. Fiml Grade. Metric Measurement: Ordering Plane Figures by Area; Making Comparisons Using a Balance; Comparing Volumes; Measuring Forces with Springs. Second Grade. Are Pictures Alwap Life Size?; Measuring Volurnw; Describing and Representing Forces; Estimations and Comparisons Using the Metric System; Separating Materials from Mixtures; Measuring Drop by Drop. Third Grade. Introduction to Temperature and Thermometem; Measuring Rate of Change--Evaporation of Water. Fourth Grade. Memorement of Volume by Displacement of Water; Units of Force; Measurement of Angles; Introduction to Probability.

In the first kindergarten exercise, Beginning Measurement-Comparing Lengths, the child arranges sticks of different lengths into sequences of increasing or decreasing lengths and learns to select objects of the same Part of a Symposium on Elementary Sclrool Science presented to the Division of Chemical Education at the 149th National Meeting of the American Chemical Society in Detroit, Mich., April 6, 1965.

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length by matching them to each other or to a third object. In the second exercise, Linear Measurement, the child uses sticks or blocks as units to measure the lengths of objects larger than the units. Metric units of length are introduced in grade one. The children learn to use a simple equal-arm balance and to use metric units of mass. They also learn to use a spring scale to measure the force of earth-pull. The idea of area is introduced in first grade and area is measured by counting the number of similar ohjectsbooks, or squares on a transparent grid-that just cover the area being measured. The participants a t the summer writing conferencesat Stanford University in 1963-64 agreed that we should include both the metric and the British-American systems since the latter is taught in schools. Several of our tryout teachers suggested that we stay with the metric system in our program. Both the teachers and the children like it. The writing group at Michigan State University in the summer of 1965 therefore decided to use only the metric system in the third experimental edition. The second grade exercise on forces not only gives the child some experience using arrows to represent direction and magnitude of forces, but also introduces him to the idea that equal and opposing forces act on objects that are at rest. In the exercises on measuring volume the child learns metric units and gets some idea of the volume of a drop of water. Measurement of temperature and of rate of change in a physical system are the subjects of the third grade exercises. In grade four the students measure volumes of solids by displacement of water. The idea that a solid can displace its own volume of water is not self evident to children of this age. This method of measuring volumes of solids is used later in grade six in an exercise on density in the operational definitions sequence. The newton as a unit of force is introduced a t this grade level. Tryout and Evaluation

The program has been prepared by a group of scientists, science educators, and teachers who met for eight weeks each summer in 196345. During the summer writing conferences, the writers were asked to consider carefully the objectives of each exercise they prepared. It was suggested that they first ask themselves, "Just what is it that I would like a child to be able to do after he has finished this exercise that he could not do before?" The answers to this question are the statements of objectives that are listed a t the beginning

of each exercise. With objectives stated clearly, it should be possible to devise simple tests to determine whether the child has achieved the desired skills. Two such tests are provided. First, at the end of each exercise there is an "appraisal activity" that the teacher uses to find out how well the children in her class have achieved the abilities. Second, each teacher is provided with a competency measure which she administers to a random sample of children after each exercise has been taught. This competency measure is the backbone of our evaluation system. The tests are simple ones and the teacher checks "yes" or "no" for each child depending on whether he does or does not exhibit the appropriate behavior. ("Point to the blue triangle." Check yes if he does and no if he does not.) The results of the testing with the competency measure are returned to AAAS where the results are tabulated by Dr. Henry Walbesser and his staff. The results of the first tryout year. when we had about 120 teachers (K-3) in 12 centers teaching the program, were encouraging. On the average, 90% of the children tested with the checklists exhibited 90% of the desired behaviors. Control children were checked, and the best results showed 50% exhibiting 50% of the behaviors. During the second tryout year approximately 80% of the children tested with the checklists attained 80% of the desired skills. The decrease between the first and second year seems to be due mainly to the increased difficulty of the revised exercises. I n the summer of 1965, a writing group composed of more than 50 participants1 revised the K-3 materials for the second time and the grade four and five exercises for the first time, and wrote new exercises for grade six. The processes for grades four through six are rooted in the elementary processes. Exercises for grades four through six develop the child's skills in these processes: formulating hypotheses; making operational definitions; controlling and manipulating variables; experimenting; formulating models; interpreting data.

are listed in Table 2. In the exercises involving changes in properties, listed in Table 2, the children are not told that they are observing chemical changes taking place. I n the kindergarten exercise, Observing 12, Observation of Color and Color Change in Plants, the emphasis is on careful and accurate observation. The children observe a colored plant, for example red cabbage, being boiled in water, notice the color changes, and the fact that some of the color goes into solution in the water. They then observe the changes in color that take place when vinegar or baking soda are added to the solution. I n the third grade exercise, Prediction 3, Case of the Suffocating Candle, the children observe the burning time of a candle under jars of different volumes. They measure the volumes of the jars and plot burning time against volume on a graph. Using this graph they then Table 1.

Excercises on the Properties of Motter

Grade Process K Observing 1 Observing 6 Observing 9

Subject Perception of color Perception of odor Observing solids changing to liquids

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... Clmsifvine: . -6 Inferring 2 Inferring 6 Communicating 10 Classifying 8 Classifying 10 Clmsifying 11 Formulating hypotheses 1 Controlling variables 5 Experimenting 1 Predicting 7

The Question of Content

Science processes are the major themes or threads around which the AAAS program is constmcted, but it is clear that process cannot be taught in the absence of content. The content has been selected from various science disciplines. I n fact, one reason for selecting science writers from biology, chemistry, physics, geology, and psychology was to provide a balance of content topics for the process exercises. I n a sense, process is the warp and content the woof of the fabric of the AAAS elementary science program. I n grades K-6 there are a t least 28 (out of 184) exercises that are related to the field of chemistry. Some of these are quite simple, but they all lead to the more intensive study of chemistry in later years. The exercises that are concerned with the properties of matter are listed in Table 1 and the exercises in which changes in properties-chemical changes-take place

2 Formulatina- hmatheses ..

Formulating hypotheses 3 Experimenting 3 Formulating models 4 Formulating hypotheses 6 Formulating hypotheses 8 Experimenting 6 Ex~erimentineX Table 2. Grade

Exercises on Changes in Properties Process

K 1

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' Two astronomers, eight biologists, seven chemists, two geologists, four mathematicians, six physicists, five psychologists, one sociologist, four education teachers (science), and 13 teachers and administrators.

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The solid. liauid. and gaseous b a t e i o f matter Differentiating between similar things The displacement of water by sir Describing an experiment (Settling of sand and pebblesin water) The odor wheel-An order arraneement A punch card system for identifying minerals Classifying and describing materials of the earth Evappration and condensatmn Thermal expansion Separating mixtures The pressure-volume relationship of air and water Air has mass and oceu~ies space The atmosphere exerts pressure Semipermeable membranes A mechanical model of a semipermeable membrane system Viscosity Small particles (An introduction to colloids) Chromatography Growin= crvst,als

Subject

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Observation of color and color change in plants

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Case of the suffocating csndle Interpreting data 2 Identifying unknowns Interpreting data 11 Effect of temperatureon rate of change Controllins variables 13 Fermentation Volume 43, Number 5, May 1966

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predict what the burning time would be under a jar of different volume from any that they tested. They then determine the burning time under that jar to test their prediction. I n the fourth grade exercise the students mix cornstarch, talcum powder, baking soda, or baking powder with water, a dilute iodine solution, or white vinegar. They observe the changes that take place when each pair is mixed. They are given an unknown solid, selected from the group of four with which they have been working, and are asked to carry out tests to identify it. In a fifth grade exercise, the students learn something about the effect of temperature on reaction rate in an exercise in which they measure how long it takes A k a Seltzer tablets to dissolve in water at different temperatures. 411 exercise on fermentation introduces them to a biochemical system. I n that exercise they identify the gas produced by a mixture of yeast and sugar as carbon dioxide, measure rate of fermentation by counting bubbles, and investigate the effect of changing concentrations and temperature on fermentation rate.

Child Pariicipation We consider the development and tryout of the

AAAS program to be a major experiment in education. The emphasis on developing skills, the clear identification of objectives and the built-in evaluation program

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are significant aspects of the experiment. How the skills are developed-whether in group activities or in individual ones-is also a part of the experiment. Some of the exercises can only be done by the individual alone, for example the fifth grade exercises on The Effect of Practice on Memorization, and Why Do We Forget?, where the child determines the effect of prnctice on his ability to remember the Latin n a m e of 20 familiar animals. Other exercises can be done hy groups. In general we have tried to emphasize activities which are done by small groups, and we have provided some equipment and supplies to the tryout teachers to encourage child participation rather than teacher demonstration. Representative of the exercises which are done by small groups is a fifth grade exercise, Interpreting Data 4, Magnetic Fields-The Nature of the Earth. Each child uses his small compass to trace the force field around a magnet which has been fastened to a large sheet of paper taped to the floor. The completed diagram is the work of a group of four or five children. Each group compares its diagram with the diagrams of other groups whose magnets were oriented in diierent directions and the class interpret their collective data. The tryout of the program is continuing in 14 centers by about 250 teachers. It is expected that a final revision of the I