Introduction to extensive reading

Harold Palmer (1917/1964, cited in Day and Bamford 1998) is credited with first using the expression extensive reading (ER) to refer to “an approach to language teaching in which learners read a lot of easy material in the new language” (Bamford and Day 2004, p. 1). Palmer contrasted this with intensive reading, by which he meant the close study of texts using dictionaries and grammars to ascertain and retain the meanings and language of the text. While it seems uncontestable that to become a good reader one must read a lot, Williams and Moran (1989) point out that most class time is spent on intensive reading – reading relatively short teacher‐selected texts, which are surrounded by pre‐ and post‐questions, vocabulary work, and strategy building activities – and very little time on allowing students to read self‐selected texts for general understanding without additional activity. As a result, instead of disliking reading because it is hard and thus doing less reading, what Christine Nuttall (1982) called the “vicious circle” of reading, students have successful experiences with texts that, with encouragement and opportunity, lead them to read more (p. 127).

ER has been defined and operationalized in many different ways. Sometimes it is defined as the reading of longer texts and sometimes as reading a lot in one subject area. These would be more accurately described as “extended reading” and “narrow reading,” respectively. Other popular reading programs have also been conflated with ER, such as “sustained silent reading,” “stop, drop and read,” or “free voluntary reading.” While each of these does share certain characteristics with ER, each does not sufficiently meet the criteria that have been used to define ER in research and practice for two decades now. In 1998, Day and Bamford boldly enumerated 10 principles of ER, and although these principles are adhered to in greater or lesser degree in ER programs around the world, they have been instrumental in shaping the discussion and the investigation of ER since they were published:

1. Students read as much as possible.
2. A variety of materials on a wide range of topics is available.
3. Students select what they want to read.
4. The purposes of reading are usually related to pleasure, information, and general understanding.
5. Reading is its own reward.
6. Reading materials are well within the linguistic competence of the students.
7. Reading is individual and silent.
8. Reading speed is usually faster rather than slower.
9. Teachers orient students to the goals of the program.
10. The teacher is a role model of a reader for students. (Day and Bamford 1998, pp. 7–8)

A recent meta‐analysis of ER research (Jeon and Day 2016) chose five of these principles (1, 3, 6, 7, and 9), as criteria for inclusion in the study, and one could argue that these five represent the core, with the others being elaborations or outcomes. In order to self‐select texts at each individual's proficiency level, there would need to be a reasonable number of texts on a variety of topics. Based on learners' prior language class reading experiences, instructors would certainly need to provide an orientation to an approach that expects them to read as they do in their primary languages, silently and for their own purposes. Finally, these practices, if well implemented, would have the potential to make reading its own reward, and, hopefully, lead to more efficient reading rates and greater comprehension in the new language. After visiting and reviewing multiple ER programs, Day (2011) himself realized that ER is not instantly pleasurable and fast. Nonetheless, he concluded that if a program did not follow most of these principles, it could hardly be considered ER.

Statistical learning

While there are likely no arguments against using reading as a significant source of input for language learning, ER has not been widely implemented in either second language (SL) or foreign language (FL) classrooms. Perhaps the single most important reason for this is the privileged role that explicit instruction receives in formal contexts of language learning, and by extension language teacher training and research on language learning. In spite of the relevant comparisons that are made between first language (L1) and second language (L2) acquisition in most discussions of teaching methodology, the implication of some of the obvious similarities are overlooked. Regardless of your theoretical orientation in terms of the starting point, mechanisms, and processes of second language acquisition, you cannot eliminate the necessity of meaningful comprehensible input and output. Likewise, no one will dispute how much more quickly one can learn if one is immersed in a context that provides a steady dose of meaningful comprehensible input and opportunities for interaction. What might be missed, though, while we work to make the classroom just such a context, are two important factors: (i) the limits of explicit instruction, and (ii) the importance of implicit learning.

By implicit learning, I am referring to the learning that happens when we are not actually paying attention to it. This is happening while we use language without too much effort for real purposes. Seidenberg (2017) points out:

Humans are data hunters and gatherers. We respond to patterns in the environment. We register repetitions and novelties, similarities and differences, the way things vary and covary, and then how things that covary covary. We experience the world as a three‐dimensional space populated by objects and events because of its statistical regularities. Language, like the visual world, exhibits statistical regularities at many levels –phonology, morphology, words, word sequences, and relations between utterances and the contexts in which they occur, among others …. For people, the algorithm of analyzing these data is learning. Every time we use language, we also update our statistical representation of it…This continual learning and updating occurs in the background as we pursue our main goals, producing and comprehending language for various purposes. Statistical learning takes place without conscious awareness or intention.

(Chapter 5, Paragraph 9)

For Seidenberg, learning by explicit means represents only the tip of the iceberg of what is needed to attain adequate proficiency for work or school. To attain the mass of learning below the surface only implicit learning will work. N. Ellis (2008) notes that explicit instruction can actually interfere with learning language features that are “more randomly structured with a large number of variables or when the important relationships are not obvious” (p. 5). The interface of explicit and implicit learning is anything but straightforward and continues to be actively investigated, but it is beyond question that we need both types of learning because they promote different aspects of language proficiency (Ellis 2005). Hulstijn (2015) adds that explicit instruction cannot speed up implicit learning, and at the end of the day he can only advise himself and others who are in the slow process of learning additional languages to “practice, practice, and practice … in a variety of communicative situations” (p. 41).

There is no intention by those who advocate for ER to undervalue explicit instruction. Research on instructed classroom learning has demonstrated there is a role for explicit/deliberate learning with adult language learners. Some have suggested that explicit learning is more effective after achieving at least a beginning proficiency through naturalistic language use, but overall adult learners are much less likely to achieve high levels of accuracy and complexity without some explicit instruction (Doughty and Williams 1998; Ellis 2006). However, instructors and curriculum designers should also consider how to increase the amount of implicit learning to which learners have access for developing language proficiency. If students engage in ER, they will be providing themselves with the large amounts of accessible language data needed for statistical (implicit) learning.

Reading and vocabulary research supporting ER

Research on L2 vocabulary and reading development particularly highlights the significant role of statistical learning. Communicative classroom activity and direct classroom instruction can certainly contribute to vocabulary growth, but there is not enough class time to even ensure that learners acquire the 3000 most frequent English words. These words account for at least 80% of oral and written texts, and for which rapid word recognition is necessary in order to process language fluently. Unfortunately, an efficient reader needs to know 98% of the words in a text (Nation 2006) to read easily for general comprehension. Large amounts of reading promote optimally spaced rehearsals, or “meetings,” with, particularly, the most frequent vocabulary in a language. In terms of the task of reading itself, Grabe (1991, 2004) synthesizes L1 and L2 reading research of the previous decade leading him to support ER as a necessary component of an L2 reading curriculum. ER is necessary to “build vocabulary and structural awareness, develop automaticity, enhance background knowledge, improve comprehension skills, and promote confidence and motivation” (1991, p. 396). Grabe (2010) adds that “overall, the L2 fluency research, while limited in number of studies, generally supports the importance of word reading fluency, passage reading fluency, extensive reading, and reading rate training on vocabulary and reading comprehension improvements” (p. 77). While there is a role for explicit training in developing some reading skills, Grabe (2017) claims that automatic word recognition, rapid sentence processing, a large sight word vocabulary, skilled strategic processing, and fluency will only develop through a large amount of engaged reading involving deliberate practice.

Research on ER

Adding to the support for ER from implicit learning, L2 vocabulary, and L2 reading research are the results of research on ER itself. The bibliography of ER research maintained by the Extensive Reading Foundation (2018) begins with the publication of a classroom study from 1917 and continues with studies related to the theory, implementation, and impact of ER on all aspects of language learning in every decade since with a noticeable uptick in activity since the 1980s. Hundreds of articles have been published in the last three decades, yet ER research has not always been taken seriously, due to methodological problems inherent in investigating implicit learning that by definition takes time to build up and is hard to measure – such as controlling all the other possible sources of input during this long period of time, operationalizing reading and reading subskills in order to measure change, and assuring that the ER program was implemented as designed. Also, once practitioners are convinced of the value of ER, there are ethical problems with withholding it from a group of students to create a control group for experimental research designs. These problems mitigate against some of the overly optimistic claims that have been made. Nonetheless, the growing body of reliable research makes a compelling argument to include ER in language‐learning contexts either as a replacement/alternative to intensive reading activity or as an additive component.

Reading comprehension

Ewert's (2012) study investigated the reading comprehension of 220 English as a second language (ESL) low‐intermediate pre‐academic students in a 7‐week 35‐hour ER program and found that they all made statistically significant gains on the reading section of the institutional placement test taken before and after each session. She also found that the gains were greater for the students who had lower reading scores to start with, thus bringing them closer to the average of reading proficiency in their cohort. Robb and Kano's (2013) investigation of the impact of ER as an additive component to the English curriculum in a Japanese university for over 2000 students across a range of disciplines and courses in two semesters revealed that, even when students did not all meet the minimum requirement of reading at least five graded readers outside class each semester, they performed statistically significantly better on a reading and listening proficiency test than a similar cohort in the previous school year across each level and in each discipline. Taylor (2014) measured the effect size for Robb and Kano's large sample size and found a strong effect not only for reading comprehension of the cohort doing ER, but also for their listening comprehension, which showed significant gains for student groups in most of the disciplines represented. While most of the research on ER has been done in FL contexts with students learning English, there is also a body of research on ER in languages other than English. For example, Hardy (2016) investigated the benefits of a short‐term elective ER course for a group of low‐proficiency Spanish FL learners at a university in the US. She found that the study participants improved significantly on a locally produced cloze‐measure of reading proficiency, but not on a broader range standardized placement test, likely as a result of the brevity of the program. Through a questionnaire on motivation and student‐guided reading journal entries, she also found that the students who participated in ER had developed stronger intrinsic motivation to read in Spanish and generally expressed satisfaction with the activity.

Reading rate

Several relatively recent well‐designed studies have investigated the relationship between reading large amounts of text and reading fluency or reading rate. In both L1 and L2 reading studies, reading rate has been found to correlate with reading comprehension such that reading too slow or too fast are not the most effective. For L2 readers, the problem is usually reading too slowly with painstaking attention to individual words. This does not add up to good comprehension. ER has been proposed as an effective means for developing reading rate without losing comprehension both because the texts are within the linguistic competence of the readers but also because they are reading for longer periods of time more often. Beglar et al. (2012) compared the reading rates and comprehension of an intensive reading group and three pleasure reading groups (n 97) in the first year (28 weeks) of university in Japan. The three pleasure reading groups read differing amounts, but in all cases they made greater gains in reading rate than the intensive reading group. The two pleasure reading groups that read the most gained the most and, in all cases, comprehension was not impacted. They also found that those using simplified texts made the greatest gains. Huffman (2014), using a similar methodology with nursing college students in Japan also found that the students with ER outperformed the intensive reading group on reading rate/fluency without any losses in comprehension.

Suk (2017) used a quasi‐experimental design to study the impact of an ER intervention in a semester long English as a foreign language (EFL) reading course with Korean university students (n 171). With two control classes and two experimental classes, Suk, as instructor, was able to give all four groups 70 minutes per week of the same intensive reading activity around the reading textbook, and in the other 30 minutes the control group received vocabulary review, quizzes, and translating challenging sentences while the experimental groups got 30 minutes of ER activity, half of which was reading graded readers. All the classes were required to engage in two to three hours of homework, which for the control classes meant more intensive reading of the textbook and vocabulary review and for the experimental classes meant ER, with a goal of reading at least 200 000 words in the semester. The reading was monitored by the students taking online quizzes for each book they completed. Although the control groups had a higher reading rate and better vocabulary knowledge in the pretests, the ER groups significantly outperformed the control groups in the posttest. They also had higher comprehension scores in the posttest even though they had started out about the same. Having carefully crafted the pretests and posttests to account for the vocabulary that the students in both conditions would actually have contact with, Suk was able to see a definite benefit of ER for vocabulary acquisition.

McLean and Rouault (2017) were able to randomly assign five classes of students at a Japanese university to two different out‐of‐class treatments: grammar translation activity or ER. One of the researchers taught all the students in the same EFL class and did not emphasize grammar translation or ER during the class time. However, every week through the two 15‐week semesters, all the students engaged in timed‐reading practice. McLean and Rouault found that the post‐treatment reading rates were significantly higher than the pre‐treatment rates for both treatment groups, but much higher, with a large effect size, for the ER treatment group, while maintaining at least a 70% comprehension level, thus making a strong case for the efficacy of ER in a reading curriculum.

Vocabulary development

There has been a considerable body of research in the last two decades on vocabulary acquisition, which supports the role of implicit learning opportunities along with deliberate learning (Nation 1997, 2011). ER is recommended based on these results, but there have not been many studies that directly investigate vocabulary learning through ER, especially not with sufficient control over acquisition from other sources of input. One of the earliest studies with SL learners (Day et al. 1991) investigated vocabulary growth after reading one reader once with 161 high school students and 397 first‐year university students in Japan. Although no claims regarding productive use or retention could be made, it was evident that target vocabulary can be learned through reading for pleasure, although the percentage of target words was quite small.

Horst et al. (1998), in a controlled book‐length ER treatment with 34 low‐intermediate English proficiency intensive English program students in Oman, found that the learners picked up more words incidentally than in previous studies, due in some measure to the fact that they read more than in previous studies. Importantly, though, Horst et al. were able to identify that the cause of the learning was not entirely related to the frequency of the words in the reading. Learners with larger vocabularies to begin with had greater gains in incidental word learning. Additionally, the learning persisted over 10 days. Nonetheless, Horst et al. cautioned against assuming that incidental learning through ER could provide all the vocabulary that learners need due to the length of time needed to grow this kind of knowledge and the randomness of which words will be known and unknown, and how frequently they will be met in a text. Waring and Takaki (2003) also found that, although learners did learn words incidentally while reading one graded reader for pleasure, the rate of learning and retention were relatively low implying that a massive amount of graded reading would be necessary to build new vocabulary with any regularity and duration.

Horst (2009) reports a quasi‐experimental study of vocabulary learning through out‐of‐school ER, but in this instance, the results of the subset of 29 adult immigrant student participants who had read at least one graded reader during the five‐week period of the investigation were compared to the subset of 18 students who had not read anything during the same period. Horst found that by individualizing the posttest measure to represent the unknown words in the particular texts that were read resulted in more robust scores for vocabulary learning than in previous studies. In this case, the ER group gained knowledge of roughly one of every two unknown words that they met in their reading. An analysis of the retention of this learning for 10 in the reading group 17 weeks later indicated that their level of knowledge of these words had not diminished. Horst also investigated the lexical access speed of the learners in relation to the frequency of words encountered in the texts. Here, too, an improvement in reaction time or fluency was observed even in this relatively short ER program.

Other benefits

The value of ER has been investigated in relation to other aspects of language learning such as listening comprehension (i.e. Robb and Kano 2013; Taylor 2014), writing (i.e. Janopoulos 1986), and grammar (i.e. Hafiz and Tudor 1990; Stokes et al. 1998; He 2014). ER has also been correlated with improvement on standardized tests like TOEFL and TOEIC, but only after long periods of ER and/or massive amounts of reading (i.e. Nishizawa et al. 2010; Mason 2006). There is no single aspect of language learning that has been more addressed in the literature on ER than motivation or affect. Although based almost entirely on self‐report data, the evidence that ER improves learners' attitudes toward reading is consistently supported (e.g. Al‐Homoud and Schmitt 2009; Suk 2016; Takase 2007, 2009). Whether this leads to more reading beyond the boundaries of the ER program is not so easy to determine.

Jeon and Day's (2016) meta‐analysis of ER research highlights some additional insights. They found that ER appears to be more effective with adult learners than with children and adolescents, and web‐based stories had a greater effect than paper books. They also found that ER as part of a curriculum as opposed to being an entirely out‐of‐school addition showed the highest mean effect for all types of ER. Interestingly, they found that ER seemed to have higher effects in FL settings than in SL settings, but this may be the result of so few quality studies of ER in SL contexts.

Obstacles to ER

Regardless of theoretical and empirical evidence of the value of ER in a second language curriculum, ER remains what Richard Day and Julian Bamford call “an approach less taken” (1998, p. 3). There are perceived and real obstacles that must be addressed. Students can be very reluctant to engage in large amounts of independent reading. They may not be able to find enough interesting, motivating, and varied materials at appropriate proficiency levels. If the texts they have access to are beyond their linguistic or cultural competence, they will not be able to make meaning from the text. Some students are not proficient readers in their primary language and may never have experienced pleasure while reading. Additionally, their previous intensive reading experiences may have led them to internalize a belief that they need to read difficult texts to learn vocabulary and grammar. Unfortunately, this is not typically pleasurable, and it results in dysfluent reading, which diminishes comprehension.

Instructors can also face serious difficulties even if they have become convinced of the efficacy of ER. They, too, may have difficulty in finding enough interesting, motivating, and varied materials at different proficiency levels to implement an ER program. Day and Bamford (1998) suggest that one can begin an ER program with as few as one book per student and 10 extras for swapping. Nonetheless, building up levels and variety of paper or online texts can be limited by budget constraints. Instructors also struggle with giving the students autonomy in their reading choices and trusting the students to honestly report what they have read. In many educational contexts, administrators, parents, teachers, and sometimes even students insist that the ER be checked in some way to avoid cheating and to confirm some level of comprehension, and this can easily lead back to intensive reading activity, thus limiting the amount of reading possible. Instructors may also face obstacles if they teach in a program that is oriented toward intensive reading with assigned textbooks that only provide short texts with skill‐building exercises. Finally, instructors are sometimes worried that students, parents, and administrators may make the false assumption that the teacher is either lazy or incompetent if they find students and the teacher quietly reading in a classroom.

Another factor that constrains administrators and instructors from adopting ER as a viable component of a reading curriculum is the current emphasis on testing and assessment. The more easily‐measurable outcomes of explicit instruction can make an argument for implicit learning challenging. Sometimes questions are also raised about the quality of materials common to ER programs. While using authentic language is undoubtedly the best source of input for language learning, texts that were written by and for advanced primary language users are typically beyond the linguistic competence of language learners. Day and Bamford (1998) suggest that engaging in authentic reading behavior is of greater value than turning an “authentic” text into a language lesson. Fortunately, at least in English, there is a large body of language learner literature that has been written for the adult language learner. With the use of insights of corpus linguistics and digital tools, such as VocabProfiler (Cobb 2018) to investigate the lexical levels in a text, new modifications of classics are also more naturalistic and yet still accessible by low‐proficiency learners.

Implementation

The most typical implementation of ER is as a course component. As such, ER is usually taught through explanation and modeling in the classroom first, and then moves to a primarily out‐of‐class activity. Other implementation models for ER include an independent course within a broader curriculum, and a co‐curricular activity supported by a self‐study center. Some instructors require a certain number of books to be read, others focus on the total number of words, and yet others require a certain amount of time to be spent in ER. Each of these has its benefits and limitations, but critical to them all is the percentage of time given to ER in the curriculum overall. Nation (2001) suggests that in any curriculum, 25% of the time should be spent on fluency development and another 25% on comprehensible meaning‐oriented input. ER accomplishes both of these curricular functions. This might be more than most could give to ER; however, in no case is 10–15 minutes here and there sufficient to be considered ER. A concentrated period of at least 30 minutes should be given at one time, and the number of times per week will depend on the nature of the curriculum overall for that period. Since in most implementations, ER is eventually done primarily out of class, the commitment of class‐time is needed at the early stages of implementation for training, and once in a while after that for some interactive or reflective activity on students' reading experiences.

Whatever the model, the role of the teacher is extremely important in implementing ER effectively. Training students in the approach is critical for ER to be effective. Because language learners typically do not engage in reading easily, it is essential that they come to understand the difference between intensive and extensive reading and to appreciate the value of each type of reading for the development of language proficiency. An introduction to ER can also include discussions of the various purposes/types of reading they are already familiar with in their primary language. Williams and Moran (1989) and Carver (2000) provide descriptions that differentiate these purposes based on the speed and repetition or skipping one does, with ER reading being the type in which one reads with relative speed, almost no repetition or skipping, and achieves about 70% comprehension for general purposes. Providing adult learners with research evidence can also help them to appreciate the value of ER. For example, the need for fluency (Beglar et al. 2012), rapid recognition of 98% of the words (Nation 2006), and the role of implicit learning for language proficiency (Ellis 2008; Seidenberg 2017) can help to convince learners to try this new approach. The instructor is also an important model, sometimes reading from the same library of ER texts as the students, or reading graded readers in an additional language she is learning. Since it takes time for learners to let go of notions they have of the superior value of intensive reading and to begin to experience success with easy texts, the instructor needs to observe closely what and how the students are reading in the early stages of an ER program. Observing students reading can sometimes make very clear which students are struggling to focus on the task. The teacher can then open a discussion with the student about interests and previous reading activity in the primary language, which, in turn, can give the teacher an opportunity to make suggestions for reading material and reading practices. Without this, students will soon be reading non‐ER materials, for non‐ER purposes, or not reading at all, and the benefits of ER will be lost.

Another important role for the instructor is to keep track of students' reading, and to help the students to participate in this process. In what Day (2011) called “pure ER” there is no testing or checking up on students regarding comprehension, but there is still the need to know what and how much they have read. Without turning this record‐keeping into a writing project that takes more time than the reading, students can also provide a quick “thumbs up or down” on the text, and how long it took them to read it depending on the ER requirements. There are a variety of ways to manage the recording‐keeping, from a paper fill‐in form to a shared web‐based form or as part of an online ER platform. A growing list of texts that they have read can be motivating feedback for the student, as is an occasional figure showing the amount of each (unnamed) student's reading up to that point in the class.

Assessment of learners in an ER program as well as the ER program itself will most likely be necessary to get buy‐in from all the stakeholders. However, the very nature of implicit learning through ER does not lend itself to immediate assessment for improvements in reading comprehension or vocabulary growth. For this reason, ER practitioners use a variety of alternative means for assessing ER either as a course component or as a stand‐alone course. While some feel compelled to have students complete short quizzes for each book they read, which are now readily available at M‐Reader (https://mreader.org) or through Xreading (https://xreadig.com), many others prefer to use a pass/fail system instead of letter grades to assess students' reading. A specific amount of time spent, words, pages, or books read, and journals or reflections submitted often make up the categories of a pass/fail system. In addition, the reading log that students keep can be monitored regularly, especially if it is a shared digital document. Sometimes, students contribute to their own final grade by providing a self‐assessment.

An important component of getting administrators and external stakeholders to appreciate the crucial role of ER in an FL/SL language curriculum is evidence of the effectiveness of an ER program over time. Other than the already published research supporting ER, an instructor can begin to collect evidence of the local value of the ER activity. Quantitative data from pre‐ and post‐placement or reading tests are going to be difficult to get unless a large number of students are included in the data pool or the measures are taken over a relatively long period of time. Qualitative evidence, however, from student reading journals and logs as well as pre‐ and post‐motivation/reading experience questionnaires is easy to collect, evaluate, and share with others.

Few classroom instructors are able to use ER as an alternative to large parts of the existing curriculum without concerns being raised by the stakeholders. However, with a modest amount of class‐time given to training learners in the purposes and practices of this approach, ER can gradually become a mostly or completely outside‐the‐classroom activity, throughout contributing to the statistical learning that explicit learning alone cannot provide. In this way, ER is best considered an approach best used at the threshold between formal and informal learning.

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