In the present study, the author attempted to clarify children’s cognition of seed dormancy, a topic which has seldom been attempted in the past, and considered the treatment of the concept of seed dormancy in elementary school science lessons.

His findings include: among fourth grade pupils (1) only one fifth of the children judged dormant seeds to be alive, (2) a few children judged whether seeds which had separated from their mother plant were alive or not by making an analogy to the human mother-baby relationships, and (3) many children did not understand the continuity of life from seed to seedling: they seemed to believe in the possibility of living organisms developing from non-living things, stating “Seeds are dead. But, when we put them in soil, they get food and water and become alive.”

According to these results, the author proposed an effective instructional strategy which focuses on children’s conception of seed dormancy.

The author has developed new experiments relating to environmental conservation using activated sludge. Research on the microflora of activated sludge has resulted in two clear observations, i.e. firstly, the ciliates such as Vorticella are usually found so it seems very easy for high school students to observe them, and secondly, the microflora of activated sludge has much in common with that of a river.

Furthermore, the author has developed simple methods of measurement of the purification ability of activated sludge by using a starch solution and milk. When using a starch solution, starch can be detected by the iodine test. When using ordinary milk, the white color of milk can be used as an indicator to measure purification ability. These same methods of measurement were also used to determine the self-purification ability of a river.

The author has incorporated the above experiments into his biology classes in a senior high school. Students observed microflora of activated sludge and measured its purification ability. Through these experiments they will be better able to consider the relation between their domestic use of water and the environmental conservation of rivers. The present research is considered to be good practice and in conformity with STS education.

The five senses games, which are useful to recognize many aspects of the nature through multiple senses such as smell, taste, touching, hearing and seeing, were developed and tested in the author’s school. These games could be played both in the classroom and in the field. Out of the classroom, the author used schoolyard and the precinct of a shrine. These games seemed to nurture children’s sensitivity to the nature because the games brought them unexpeced suprises to the nature.

As most of the games developed in the present study need wild herbs and grasses, a wild grass garden is desirable in case of urban schools. Then pupils can play these games safely in the schoolyard, and it allows teachers to utilize these games easily in their teaching. As any special knowledge of the nature is not required, any teacher can lead children in the games. The five senses games are, therefore, applicable to science (“Rika”) education, life environment studies (“Seikatsuka”) education, education for the handicapped and environmental education including field education.