What is already known about this topic

Increasing access to books has mixed effects on children’s reading skills.

What this paper adds

Instruction on reading strategies in addition to access to books results in positive impact on Grade 3 migrant students in China.

Implications for theory, policy or practice

In addition to increasing access to books, teach students reading strategies.

Reading skill development in early elementary grades is of vital importance. Reading lays a foundation for learning content areas such as mathematics, science, and social studies. It is, therefore, closely linked to academic success and thus to life success, given the essentiality of a college degree in the current society (Lesaux et al., 2010; Hernandez, 2011; National Center for Education Statistics, 2011; Sparks et al., 2014). A few studies have emphasized the importance of reading at grade level by third grade. Students below grade level in third grade are more likely to experience learning difficulties and behavioral problems at school and have lower probabilities of graduating from high school and attending college than their more capable peers (Lesaux et al., 2010; Lesnick et al., 2010). This is likely due to the transition from learning to read by the end of third grade to reading to learn from the beginning of fourth grade. The demands for comprehending the written material substantially increase in upper elementary grades, making it more difficult for struggling readers to succeed at school (Annie E. Casey Foundation, 2010). It may explain why remedial programs for struggling readers are more successful if implemented before third grade (e.g., Foorman et al., 2003; Annie E. Casey Foundation, 2010; Sparks et al., 2014) and it is critical to support language and reading development in primary grades.

Despite the significance of early reading development, reading resources tend to be inadequate in developing countries, or at least for children in certain regions of these countries. Take China as an example. Studies found that, while about two-thirds of the families in large cities bought about 10 children’s books each year and children in cities, on average, read over 10 books each year (Li, 2016), only about 30–40% of the families in rural China had 10 or more children’s books at home and less than 1% had 25 or more (Gao et al., 2018; Yi et al., 2019; Wang N. et al., 2020). What makes the matter even worse is that children in remote rural areas in China have little access to public libraries and bookstores, which further restricts their reading resources (Wang H. et al., 2020; Wei, 2021). In fact, three-fourths of the rural children surveyed in a study listed “limited reading resources” as a barrier to independent reading. In contrast, only about one-third of the urban children made the same claim (Wei, 2021). Not surprisingly, children in rural areas have been found to be low in reading achievement. Researchers assessed rural primary school fourth-graders/rising fifth-graders with items from the Progress in International Reading Literacy Study (PIRLS) test and found that rural primary schoolers on average scored lower than the PIRLS participants from all 44 countries and regions (Wang N. et al., 2020; Gao et al., 2021, 2022).

These previous studies in China are predicated on the hypothesis that reading volume or quantity is important to students’ reading skills because reading experience provides an opportunity to practice reading (e.g., decoding) and helps gain world and content knowledge, both of which are essential for reading skills. However, studies examining the effects of increasing reading experience and opportunity have produced mixed results (see Allington and McGill-Franzen, 2021 for a review). For instance, programs that provided both reading materials and teacher professional development in reading instruction produced positive effects on students’ reading achievement in the Philippines and Rwanda (Abeberese et al., 2014; Friedlander et al., 2019). Similarly, a summer reading program conducted in the United States improved students’ performance on the year-end state reading test, although not their performance on the reading assessments administered in the fall semester immediately after the summer vacation (Stein, 2017). Yet another program implemented in the United States exerted no overall effect, but a more nuanced analysis indicated that it produced positive effects for high-poverty schools and negative effects for moderate-poverty schools (White et al., 2014). A meta-analysis of 67 studies conducted in low- and middle-income countries indicates an overall positive effect of explicit and systematic literacy interventions, including increased access to reading materials, on reading skill development (Kim et al., 2020).

Reading intervention programs implemented in China have also delivered mixed results. For example, Gao et al. (2018), using a matching method, found that a program combining an in-class library with high-quality teacher training (“focus[ing] on instructing students on how to read independently”) improved not only students’ reading skills (measured with reading items adopted from PIRLS and translated into Chinese) but also their mathematics and Chinese language arts test scores (assessed with standardized mathematics and Chinese language arts tests developed by the researchers with assistance from local educators); in contrast, a program that provided only books and a program that combined an in-class library with low-quality teacher training (“focus[ing] primarily on how to instruct Chinese language classes in the manner mandated by the national curriculum”) exerted no effects (p. 114). Using a randomized control trial, Yi et al. (2019) found that an in-class library program had no effect on students’ reading or academic achievement, but it improved their reading habits and their attitudes toward reading though decreasing their reading confidence. Also employing a randomized control trial, Guo et al. (2021) found that providing free books for summer reading improved students’ word reading performance and summer reading amount but not their reading comprehension performance. The program was particularly beneficial to low-performing students and students who had parents with limited education.

Intervention programs targeted at socioeconomically disadvantaged children in China have mostly been implemented in rural areas; very few are intended for migrant children, i.e., children who moved to cities from rural areas along with their parents. There are more than 14 million migrant children in the compulsory education system in China, with the number increasing every year (Ministry of Education of the People’s Republic of China, 2018, 2019, 2020, 2021). It is difficult for these children to enter local public schools because of the unique household registration (hukou) system in China; many of them can only go to private schools specifically for migrant children (i.e., “migrant schools”). Migrant schools in China in general are characterized by poor educational resources and inferior teaching quality, many staffed with “under-qualified and unmotivated teachers with high job turnover” (Lai et al., 2015, p. 36). As a result, children in these schools do not perform as well as local children, migrant children in urban public schools, or even children in rural public schools (Chen and Feng, 2013; Lai et al., 2014; Afridi et al., 2015; Lv and Wang, 2017; Wang et al., 2017).

Many prior reading interventions focused on increasing students’ access to books (see above). However, although access to books is necessary, it may be insufficient for improving students’ reading skills if it is not accompanied by quality reading experiences. One of the consistent results in the field of reading is that students’ knowledge of how to read (reading strategies) is important to their reading skills (see Shanahan et al., 2010 for a review). For example, using graphic organizers and understanding text structure (e.g., characters, problems, and solution) support students’ comprehension (e.g., Kim et al., 2004; Bogaerds-Hazenberg et al., 2021). Strategies of activating background knowledge, questioning, summarizing, searching for and organization information can help reading comprehension (Guthrie et al., 2004; Guthrie and Klauda, 2014). Therefore, in the current study, we examined whether instruction on reading strategies and reading activities makes a difference over and above access to books for migrant children in China.

Extant literature suggests that the impact of reading interventions is not uniform, but instead is moderated by factors such as parental education level, prior reading performance, and urbanicity of the area where the intervention was implemented (Kim et al., 2020; Guo et al., 2021). Research has found that intervention results tend to be larger for students with lower academic performance, and lower performance has been found to be associated with biological sex, parental education, access to books, and family mobility (Zhang and Guo, 2011; Kim and Quinn, 2013; White et al., 2014; Guo et al., 2021).

Research examining differential impact has mostly focused on students’ demographic backgrounds (e.g., differential effect as a function of biological sex, parent education, prior achievement), as described in the preceding paragraph. In the present study, we extend previous studies by examining the impact of intervention on different types of reading comprehension. Reading comprehension is widely classified as shallow/literal comprehension and deep/inferential comprehension. Shallow/literal comprehension refers to recall or retrieval of explicitly presented information whereas deep/inferential comprehension refers to understanding of the text including inferring, interpreting, and evaluation information (Mullis and Martin, 2019). Not surprisingly, there are different types of items in reading comprehension tasks that are designed to tap into literal and inferential comprehension, and those are widely classified into literal, inferential, and evaluative ones. These types are aligned with the PIRLS Framework for Assessing Reading Achievement (Mullis and Martin, 2019). These represent different levels of cognitive demands placed on the reader and varying levels of interaction with the text required of the reader (Herber, 1970). For literal comprehension, a reader simply needs to recall information explicitly stated in the passage (Carnine et al., 2010). For inferential comprehension, a reader needs to infer information that is not explicitly stated in the text, including interpreting the author’s meaning, inferring meaning by relating what they have read in the text to their prior knowledge and experiences, and establishing relationships between elements in the text by “reading between the lines” and connecting information dispersed throughout the text (Vacca et al., 2009; Carnine et al., 2010; Basaraba et al., 2013; Kim and Petscher, 2021). For evaluative comprehension, a reader needs to move beyond the text and evaluate it critically (Rupley and Blair, 1983; McCormick, 1992; Basaraba et al., 2013; Mullis and Martin, 2019). Literal comprehension is indispensable as it establishes foundational understanding of the texts for higher-order comprehension such as inferential and evaluative comprehension (Basaraba et al., 2013). However, literal comprehension relies on recall while it is higher-order inferential and evaluative comprehension that are essential for deep comprehension of texts and learning. Therefore, investigation into students’ performance on different types of reading comprehension would provide more nuanced information on the impact of a reading intervention program.

We examined whether the treatment and control groups were equivalent on demographic characteristics and found the two groups comparable. As can be seen from Table 1, the two groups were not statistically significantly different in student or family characteristics.

With a randomized control trial, we examined the effects of a reading strategy instruction program on reading skill development for third-grade migrant children in migrant schools in Beijing, China. We randomly assigned classes to the treatment group and the control group. Each semester, the Chinese language arts teachers in the treatment classes received two-hour training in reading instruction and then spent 70–80 min in class instructing students how to read a book provided, for two consecutive semesters. In contrast, the teachers of the control classes would teach business-as-usual. Students in these classes also received the same book each semester and therefore, the only difference between the conditions was the reading strategy instruction. Overall, students in the reading strategy instruction condition performed higher than those in the business-as-usual condition. Interestingly, what drove the differences in the overall reading performance was students’ performance on inferential comprehension. In addition, the effects were significantly larger for students who did not live in Beijing prior to starting elementary school than for their peers.

The treatment group outperformed the control group in the overall reading comprehension by 0.18 standard deviation. Direct comparison of this effect size to other interventions is difficult due to differences in study populations, contexts and settings, duration, and target intervention. For example, many studies in developing countries had multi-component interventions where multiple skills were addressed (e.g., word reading, emergent literacy skills in addition to reading comprehension; see a meta-analysis by Kim et al., 2020). With this caveat in mind, the effect size of the present study is in line with previous reading comprehension interventions. For example, a 31-day reading program implemented in the Philippines, which provided both reading material and teacher training, yielded an effect size of 0.13 (Abeberese et al., 2014). A two-year intervention program implemented in rural Rwanda compared the school-only and lifewide-learning approaches to supporting early-grade learning (with the latter approach including a community component) and found an effect size of 0.21 for the former and 0.33 for the latter (Friedlander et al., 2019). Meta-analyses also produced similar results: Kim and Quinn (2013) found a mean size of 0.23 for effects of summer reading programs on reading comprehension in the United States and Canada; McEwan (2015) a mean effect size of 0.12 for teacher training in developing-country elementary schools; and Kim et al. (2020) a mean effect size of 0.25 for literacy interventions on reading comprehension in low- and middle-income countries. The program reported in this study was fairly effective considering the facts that it did not require extensive amount of teachers’ time in either training or in-class reading instruction and that the study included a rigorous comparison where students in the comparison condition received books.

It is a highly encouraging finding that the treatment classes performed significantly better than the control classes on inferential comprehension although the two groups’ performance was comparable on literal comprehension. This indicates that the treatment classes outperformed the control classes on higher-level comprehension of making inferences about meanings not explicitly stated. Inferential comprehension is generally more cognitively demanding than literal comprehension and is a more advanced comprehension (Kintsch and Rawson, 2005; Nation, 2005; Basaraba et al., 2013). The importance of inference making in successful comprehension is highlighted in theoretical models of reading comprehension (e.g., Kintsch and Rawson, 2005; Perfetti and Stafura, 2014; Kim, 2020) and associated large body of literature (e.g., see Cain and Oakhill, 2007 for a review). The larger impact on inferential comprehension by the intervention suggests that beyond support for access to book, it is important to provide reading instruction on reading strategies during independent reading. These results are in line with previous evidence that reading strategy instruction improves students’ reading comprehension skills (Shanahan et al., 2010), but also show that what drives the improvement of reading comprehension is higher-order inferential comprehension at least for third grade students from migrant families in China.

Another notable finding is that the program had a differential effect as a function of whether students live in Beijing or not before they started elementary school. Children who did not live in Beijing prior to elementary school benefited more from the intervention. These results might be because these students’ families had been more mobile than their peers’, and family mobility was negatively associated with children’s reading performance, probably because constant mobility interrupted children’s learning and forced them to keep adjusting to new environments (Zhang and Guo, 2011). Alternatively, these findings may be because these children’s place of stay had been less educationally favorable than Beijing, as children in remote rural areas tend to have very limited access to reading resources (Wei, 2021). No matter what the reason may be, these children were likely to have a lower starting point in reading. In fact, regression results indicate that living in Beijing prior to elementary schools was positively associated with reading performance (Table 2). The results are encouraging that the program narrowed the reading achievement gap between the two groups of students. This is consistent with prior findings that intervention programs tended to produce greater effects for students at a disadvantage, in terms of socioeconomic status and prior performance (Kim and Quinn, 2013; White et al., 2014; Guo et al., 2021). Future studies are needed to find the mechanism explaining the differential effects.

Another unique aspect of the study is an explicit examination of a potential spillover effect, and we found evidence of some spillover effects. The treatment effects were smaller for the classes taught by the five teacher trainees who each taught a treatment class and a control class even though they did not instruct their control classes how to read the two books provided. These teacher trainees might intentionally or unintentionally have introduced reading strategies and employed teaching activities that they had learned from the training. As a result, positive reading behaviors might have also been encouraged in the control classes that they taught. The observed spillover effect is a concern for RCTs. On the other hand, however, the results also suggest students may benefit from their teachers’ training in reading instruction even when teachers do not allot in-class time to specifically and formally focus on reading instruction.

This study has other limitations. One notable limitation is that, as stated earlier, we could not administer pre-test at the beginning of the school year because of the COVID-19 pandemic. As a result, we could compare the treatment group and the control group only on personal and family characteristics but not on reading skills before the program was implemented. Although it is not highly unusual for RCTs not to include pretests, future research could replicate this study with a pre-test component.

To our knowledge, this is one of the first studies to explore the possible effects of reading programs on the early reading development of migrant children in migrant schools in China. Reading strategy instruction made a difference in overall reading performance and, in particular, performance in inferential comprehension. The findings are encouraging for researchers and practitioners intending to foster the reading development of migrant children in migrant schools, especially migrant schools located in large cities. Explicit reading strategy instruction supported by teacher professional development in addition to access to books can be a potential way to improve the reading skills of migrant children in migrant schools, an important segment of the population in China.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

Ethical approval was not required for the study involving human participants in accordance with the local legislation and institutional requirements. The research was conducted with full cooperation from the schools involved. Written informed consent to participate in the study was provided by the participants’ legal guardians/next of kin.

QG obtained the grant and designed the study with the co-authors, and conducted data analysis. Y-SK made contributions to conceptualization and writing. YL, YP, WS, JY, and LY contributed to conceptualization, implementation, data collection, and analysis. All authors contributed to the article and approved the submitted version.

The work reported here was funded by the National Natural Science Foundation of China (grant 71874094) and the Tsinghua University Initiative Scientific Research Program (grant 2015THZWYY06) to QG. The authors are grateful to all the participants for their support of this study.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.