An examination of the utility of the Aozora Repository to support reading comprehension development, reading fluency, and extensive reading for L2 learners of Japanese

Despite a recent boom in the development of graded reading materials for L2 Japanese learners which can be used for extensive reading (ER), the total amount of material remains low, and the highest stated vocabulary level of these texts is only 4500 words. However, achieving a 95% coverage rate of tokens in Japanese texts requires knowledge of 9500 word s (Matsushita, 2014) – a substantial gap between these graded texts and what is needed for independent reading. To meet learner needs to move beyond the beginner reading level while engaged in ER, the free digital collection of copyright-free literature known as “Aozora Bunko” was assessed to determine if, based on vocabulary coverage profiles, there might be a significant number of texts that would be useable for L2 Japanese learners. Of 18,552 works analysed, nearly 3400 were found to have a 95% vocabulary coverage level of between 1500 and 9500 words, indicating they may be suitable for learners for Japanese ER and may be able to bridge the gap between beginner texts and independent reading. The method demonstrated in this paper may be useful for instructors of other languages seeking to increase the volume of material available for their learners.