海洋酸性化によって石灰化生物が行う炭酸カルシウムの形成が阻害されることを観察できる実験教材の開発と高等学校での授業実践による教材の評価

抄録

The progress of ocean acidification caused by an increase in the CO₂ concentration in the atmosphere inhibits calcium carbonate formation of calcifying organisms by decreasing the CO₃^2– concentration in sea water. In this study, we conducted experiments to obtain the data required for the development of experimental teaching materials on inhibition of calcium carbonate formation by calcifying organisms. Using the results of these experiments, teaching materials on inhibition of calcium carbonate formation by calcifying organisms, which can be used in regular science classes, were developed. The teaching materials developed consist of (1) “Heat the shells strongly with a burner to make CaO and then generate an CaCO₃ aqueous solution using it”, (2) “Dissolve some different volumes of CO₂ in the CaCO₃ aqueous solution” and (3) “Observe that after dissolving CO₂ the CaCO₃ aqueous solution changes from transparent to cloudy to transparent in the order of the dissolved volume”. To evaluate the teaching materials developed, a science class using them was implemented in senior high schools, and questionnaires were given to students before and after classes. The results of the questionnaires indicate that the developed material is effective for environmental education.