ER increases reading skills, speed and understanding.
Aka, N. (2018) Reading performance of Japanese high school learners following a one-year extensive reading program, Reading in a Foreign Language 31(1), 1-18. Available: https://nflrc.hawaii.edu/rfl/item/414
Here is a short PPT that summarizes the results.
Suk, N. (2017).The effects of extensive reading on reading comprehension, reading rate, and vocabulary acquisition. Reading Research Quarterly, 52(1), 73-89. https://ila.onlinelibrary.wiley.com/doi/full/10.1002/rrq.152
Robb, T., & Kano, M. (2013). Effective extensive reading outside the classroom: A large-scale experiment. Reading in a Foreign Language, 25(2), 234-247. http://nflrc.hawaii.edu/rfl/item/281
ER builds vocabulary.
Waring, R. & Takaki, (2003 October) At what rate do learners learn and retain new vocabulary from reading a graded reader? Reading in a Foreign Language (15),2.
http://nflrc.hawaii.edu/rfl/October2003/waring/waring.pdf
Rodrigo, V. (1995, March) Does a reading program work in a foreign language classroom? Paper presented at the Extensive Reading Colloquium, American Association of Applied Linguistics, Long Beach, CA.
Hafiz, F.M. & Tudor, I (1990). Graded readers as an input medium in L2 learning, System, 18 (1), 31-42.
https://www.sciencedirect.com/science/article/pii/0346251X90900262
ER expands grammar knowledge.
Rezaee, A. & Nourzadeh, (2011, September) S. Does Extensive Reading Improve EFL learners‟ Processing Ability? Theory and Practice in Language Studies, 1 (9), pp. 1167-1175,
http://www.academypublication.com/issues/past/tpls/vol01/09/14.pdf
Aka, N. (2018) Reading performance of Japanese high school learners following a one-year extensive reading program, Reading in a Foreign Language 31(1), 1-18. http://nflrc.hawaii.edu/rfl/item/414
ER develops listening and speaking ability.
Cho, K.-S., & Krashen, S.D. (1994) Acquisition of vocabulary from the Sweet Valley Kids series: Adult ESL acquisition, Journal of Reading, 37 (8), 662-667
http://www.sdkrashen.com/content/articles/1994_sweet_valley_high_with_kscho.pdf
Improves writing ability.
Day, R.R. (2010). The Benefits of Extensive Reading. OUP Bookworms site, Spain. Available from https://www.academia.edu/download/32166076/benefits_of_reading.pdf
Janopoulos, M. (2009). Pleasure reading and writing in a second language: (How) Can we make the connection? In A. Cirocki (Ed.), Extensive reading in English language teaching (pp. 429-438). Munich, Germany: Lincom.
Mermelstein, A. D. (2015). Improving EFL learners’ writing through enhanced extensive reading. Reading in a Foreign Language, 27(2), 182-198.
ER correlates with improvement on tests like the TOEIC.
Nishizawa, H., Yoshioka, T., & Fukada, M. (2010). The impact of a 4-year extensive reading program. In A. M. Stoke (Ed.), JALT2009 Conference Proceedings. Tokyo: JALT.
http://jalt-publications.org/archive/proceedings/2009/E035.pdf
ER increases student enjoyment of reading.
Elley, W.B. (1991). Acquiring literacy in a second language: The effect of book-based programs. Language Learning. 41 (3) 375-411.
Cho, K.-S., & Krashen, S.D. (1994) Acquisition of vocabulary from the Sweet Valley Kids series: Adult ESL acquisition, Journal of Reading, 37 (8), 662-667
http://www.sdkrashen.com/content/articles/1994_sweet_valley_high_with_kscho.pdf
Rodrigo, V. (1995, March) Does a reading program work in a foreign language classroom? Paper presented at the Extensive Reading Colloquium, American Association of Applied Linguistics, Long Beach, CA.