Language of instruction at school: supporting mother tongue teaching vs later acquired language teaching
While there are numerous studies providing evidence for the use of mother tongue (MT) instruction for reading outcomes, there are only a limited number of studies discussing the evidence on the impact of language of instruction (LOI) transition policies on biliteracy and multilingual literacy outcomes. This study is the first systematic review of this evidence.
What is this review about?
Over the last 50 years, schooling has expanded dramatically in most low- and middle-income countries (LMICs). However, while children are in school more than ever before, a large proportion of students are not acquiring basic literacy and numeracy skills. Although a myriad of factors contributes to this state of learning poverty, the role of language is essential as all learning happens in and through language.
LOI policies focus on the mandated language teachers should use when teaching students in the classroom. This review looked at whether MT-based LOI and language transition policies facilitated reading and biliteracy and multilingual literacy outcomes for students and whether these policies have different effects on skill development by language group.
What is the aim of this systematic review?
This Campbell systematic review examines the effects of language of instruction polices on students’ literacy, biliteracy and multilingual literacy skill development in low- and middle-income countries.
What studies are included?
The review summarizes evidence from 45 high-quality studies, including 11 randomized controlled trials, 11 quasi-experimental studies, seven cross-sectional studies, and 16 qualitative studies.
The included studies evaluate the effects of MT-based LOI and LOI transition policies on students’ biliteracy and multilingual literacy skill development. The studies spanned the period from 1995 to 2020 and were carried out in sub-Saharan Africa and South- and Southeast Asia.
Does prescribing mother tongue-based instruction in primary school lead to improved literacy and biliteracy outcomes for students in bilingual and multilingual contexts?
Meta-analyses and quantitative narrative syntheses indicate that MT-based LOI interventions may improve students’ letter knowledge, word reading, sentence reading, and reading comprehension in the students’ MT, improve students’ word and sentence reading, and reading comprehension in the national language, and improve students’ oral language proficiency, word, and sentence reading, reading comprehension, and writing in the later acquired language.
It is still unclear to what extent MT instruction can support English (or a later acquired language) compared to investments in high quality teaching in the later acquired language alone.
Furthermore, the systematic review revealed an evidence gap on how MT-based programs may impact later language literacy acquisition.
What factors affect how well mother tongue-based language of instruction policies work for biliteracy outcomes?
The qualitative studies suggest that high-quality teaching and learning materials in the MT coupled with improved curriculum and bilingual materials throughout the classroom are necessary for a successful MT-based LOI program.
These programs overwhelmingly received positive reception and wide support by students and teachers alike as students and parents perceive that these programs improve teaching quality, increase student motivation in the classroom, and respondents report improvements in bilingual reading skills.
What do the findings of this review mean?
MT-based LOI policies are likely to positively affect students’ literacy outcomes in their MT, but the evidence base is small and restricted to more costly interventions.
The evidence is still inconclusive on how much MT instruction can support English (or later acquired language) relative to high quality teaching in the later acquired language. There is an evidence gap on the impact of MT-based policies on transition and later language outcomes.
The findings from a limited quantitative evidence base suggest that high-quality MT interventions may lead to gains in MT reading outcomes. Qualitative results showed that students felt that their English improved in programs for English as a later acquired language.
Given the lack of conclusive evidence on the trade-off between supporting high-quality English LOI versus high quality MT LOI with a later transition to English-medium education, more research is needed.
How up-to-date is this Campbell review?
The review authors searched for studies up to 2020.