Abstract
This study is an attempt to analyze the “logic of composition of teaching materials” using Toulmin’s argument model for elementary school science textbooks. For three typical textbooks currently in use, descriptions that lead to conclusions from the data were extracted. As a result, a total of 198 arguments were identified. Of these, only 19 arguments (9.6%) were accompanied by warrants, and for most arguments, the warrants were hidden. The leap from data to conclusion was categorized into three categories: “generalization to higher categories”, “divergence between phenomenon and interpretation”, and “divergence between models and real objects”. These results suggest that there are certain flaws in the logic of the textbooks, and that if learners cannot fill the leap, they are likely to fail learning. It was also argued that simply “restoring” the hidden warrants would result in a paradox of question-begging in which the content to be learned in the future becomes the warrant for the current argument. Furthermore, several measures were proposed to increase the reliability of the argument while avoiding the paradox.
https://ror.org/01dq60k83 
