This study was conducted to analyze how students make sense of science through small-group discussions. The focus was on the process of turn-taking observed during such discussions. While large-group discussions tend to be organized, small-group discussions tend to be disorganized, that is, characterized by overlapping discourse. However, the overlapping discourse helps the students make sense of science. Back-channel discourse, conflicting discourse, and cooperative discourse are three types of overlapping discourse that contribute to scientific sense-making. 1. Back-channel discourse encourages speakers to share and reinforce scientific understanding, thus allowing them to continue and promote discourse. 2. Conflicting discourse encourages speakers to understand different points of view, thus allowing them to reassess their understanding of science. 3. Cooperative discourse encourages speakers to integrate their thoughts, thus allowing them to synthesize their understanding of science.

We investigated students' individual cognitive styles of observation of geological strata in a social context. First, we examined the field-independent and field-dependent cognitive styles of the students. Then, we categorized the students'cognitive styles in their social context. The number of field-independent and field-dependent cognitive style students was equal. Next, the students organized themselves into pairs and observed strata for ten minutes, discussing their observations freely. We used four sheets of photographs on the strata in the Tertiary level, and we recorded these discussions. We analyzed first which cognitive style student the students chose as their partner: field-independent or field-dependent. As a result, we found that they chose students with a cognitive style different from their own. Next, we examined the observations of the students. Did they observe microscopically or macroscopically? We examined whether students with field-independent or field-dependent cognitive styles produced these observations. We paid special attention to students with field-dependent cognitive styles. All of them were students who had been categorized as such by their teachers. They were observing macroscopically. However, their actual cognitive style was field-independent. Their tendency for observation changed according to the social context in which the teacher placed them. Therefore, we concluded as follows: ・When two students participate in the observation of geological strata, they are influenced by the social context presented by a teacher and tend to choose student partners with a cognitive style different from their own. ・In the observation of geological strata, students with field-independent cognitive styles were influenced by the social context presented by the teacher and tended to observe macroscopically.

The level of pollution of a river is measured by using creatures living in that river, a method widely used nowadays in Japan. Though the water creatures used in this method are generally benthos, fish, algae, aquatic plants and bacteria, in this research project, the relationship of fish and water quality was examined with the aim of developing teaching materials. Fieldwork observations were made from July to September 2000 at 32 points of 20 rivers inside Aichi Prefecture. A biological water class was determined by observing and measuring the water temperature, COD, PO4, NH4-N, and fish captured were with a net, mondori. Fish couldn't be found in two points. But in 30 points, 27 kinds of fish were captured, including high appearance frequency fish such as field gudgeon, pike gudgeon, topmouth gudgeon, Japanese fatminnow, dark chub, pile chub, crucian carp, carp, Asian pond loach, and lizard goby. The relationship of water quality and fish was then examined. The relationship of fish and biological water class, COD, PO4 and NH4-N, was determined. From this relationship, it became clear that fish could be used as an index creature of the water quality of a river. From the result of this investigation, a procedure of judging water quality could be developed. We think that the measurement of river environment using fish is an effective teaching material for environmental education in elementary, lower and upper secondary schools.

The purpose of this research is to examine the learning effects of the "products creations" method through teaching sounds to first graders of a lower secondary school. In order to test these effects, we compared an experimental group's lessons using the "products creations" method and a control group's lessons using materials prepared by the teacher. As a result, it was found that "the products creations" method produced the following two effects: 1) students could construct scientific concepts more accurately, and 2) students discovered many new problems to be solved.

The purpose of this research was to investigate the actual practice of both observation and experiment described in lower secondary school science textbooks. The questionnaire examined to what extent each of 128 teachers was utilizing the five stages of observation and experiment described in the textbook: explanation, video, demonstration, group experiments, and individual experiments. According to the responses, the combined overall rate of those students aged 12-15 (that is, grades 1 to 3 inclusive) who used the observation and experiment approach in the categories of "group experiments" and "individual experiments" by field is as follows: chemistry (78%), physics (62% ), biology (57% ), and earth science (32% ). There were a few differences noted in the responses received according to gender, and more experienced teachers tended to focus more on chemistry and physics than on biology and earth science. The individual specialties of the teachers were represented among the grade levels and the four fields. The teaching of all four fields is a fundamental part of the course of study at the lower secondary school level, and it was found that the science teacher's individual specialty did not affect his or her instruction.