The objective of this study was to clarify a way of evaluating students’ holistic processing of electric circuits by using neural networks. Ninth grade students were asked to perform a holistic processing test and an analytic processing test. As a result of correlation analysis, there was no clear relationship between holistic processing and analytic processing. As a result of performing neural networks analysis, many students believed that the electric current increases when batteries are connected in series, but they didn’t believe that the electric current would increase when resistors are connected in parallel. In fact, many students believed that the electric current decreases whenever additional resistors are connected.

The purpose of this study was to investigate the effect of different structures of elementary school science curricula on the development of elementary school students’ concept formation and understanding of electromagnetism. On the basis of the comparison, the following findings were obtained in two investigations of students’ conceptual understanding carried out under the implementation of the revised courses of study in 1968 or 1989. (1) Although the correct answer rates of present students were generally lower than those of twenty years ago, the gaps were not large. And there was no remarkable difference in their answer selection patterns according to their grade levels. It was considered that these results were not due to any difference in the concept formation routes of the students but to the difference in their attainment levels in the same route. The influence of the sequence of curricula on their concept formation was not found to be macroscopically significant. However, short period changes appeared in the answer selection patterns of the students in the grades that underwent content revision. (2) We found that the experiences of present students had decreased qualitatively and quantitatively. Since discernment and classification activities in the early basic stage of learning were emphasized less than before, the ability of students to conceptualize had not developed adequately. In regard to this point, the influence of the scope of the curriculum on concept formation was considered to be large.

When high school students study topics in biology such as development and heredity, it is very important for them to recognize the life history of creature. However, teachers have not given sufficient attention to this crucial aspect. We conducted an investigation to grasp how students recognize the life history of a familiar and popular creatures, the beetle. The results included the following three naive conceptions; (1) about half of the students surveyed answered “The Imago beetle hibernates”; (2) around 10% answered, “Young beetles live together with their parents”; (3) one even replied “In winter females hibernate, but males die”. We found that it is necessary to give adequate attention to the life history of creatures when preparing teaching materials when they study biological domain such as development and heredity.

The purposes of this paper are the next two points. First, to make clear how the use of contrasting materials is the most effective way to teach the target material, we examained the development of students’ understanding fo the conservation of mass in a water solution through the presentation of several contrasting materials at the same time. Next, in accordance with this result, we proposed a teaching strategy and verified its efficacy. As a result, the findings of this study are as follows: (1) The most effective material to demonstrate the conservation of mass in a water solution is clay. (2) However, the use of clay by itself is not sufficient for the demonstration of this concept. (3) The class introducing the teaching strategy of using contrasting materials such as sand and wood at the same time was effective.