A Quantitative Analysis of Conceptual Explanations in Science Textbooks

Proposal and Implementation of Analytical Metrics

Abstract

This study analyzes textbooks as the primary medium for conveying a knowledge base in the context of compulsory education. It introduces a quantitative measure for assessing conceptual explanations and visualizes changes across grade levels. The analysis focuses on science textbooks from Grade 5 to Grade 8, examining three key elements: term types, the number of definition expressions, and the number of classification expressions. The findings reveal that elementary school textbooks devote more sentences and words per term compared to middle school textbooks. While term types were analyzed as a surface-level cue for concepts, the number of definition expressions—representing explicit conceptual explanations—did not align with term types. Elementary school textbooks demonstrated a significantly lower proportion of explicitly defined terms compared to middle school textbooks. Furthermore, the number of definition and classification expressions, which provide explicit conceptual explanations, increased approximately fourfold from Grade 6 to Grade 7. The study contributes to quantitative linguistic research on educational texts and offers a foundation for evaluating the clarity and accessibility of conceptual explanations in school curricula.