Readability, logodiversity, and the effectiveness of college biology textbooks

Background/Question/Methods

I tested whether either the amount of technical vocabulary or the readability (as determined by grade level indices) had a significant effect on students’ ability to learn general biology concepts, such as population dynamics, from readings. After reading one of three alternate versions of standard readings taken from a general biology textbook, students took a standard quiz. This was repeated to cover a total of four topics during the semester.

Results/Conclusions

Decreasing the amount of technical vocabulary significantly increased students’ reading comprehension in one of the four units. Textbooks did not appear to be an important source of learning for students in this study; fewer than half the students reported that they were reading the assigned chapters near the start of the semester, and this number declined sharply. Students had difficulty correctly answering questions immediately after reading brief selections, indicating a low level of comprehension. Changes in textbooks and teaching strategies may improve student learning and reading compliance.