Abstract
Science textbooks of junior and senior high schools of the following countries were analyzed : China, France, Germany, Indonesia, Singapore, and the U.K.. Ions and related subjects such as acids/bases, dissolution, oxidation/reduction, and electrochemistry were investigated as examples. It was found that the subjects are studied spirally and on a step-by-step basis throughout secondary education in these countries. Step-by-step and spiral education in science are effective, and important and/or everyday concepts should therefore be introduced at an early stage, which is in contrast to the underlying policy of the upcoming Japanese national curriculum standard given by the Ministry of Education, Culture, Sports, Science and Technology.
