A major policy change in early education in the Philippines led to an unexpected drop in test scores and academic achievement—revealing the challenges that even well-intentioned reforms can have and the importance of wisely investing in the first years of learning.
The "natural experiment" came about in 2012, when the Philippine government introduced the Mother Tongue-Based Multilingual Education (MTB-MLE) program, which required public schools to teach kindergarten through Grade 3 students in a native language chosen from a list of 19 languages spoken across the country. While the policy was well-intentioned, seeking to expand the use of local languages, it unexpectedly led to a decline in the overall quality of education across the country.
A new study by Ford School and Economics Professor Dean Yang and Economics PhD student Thomas Lloyd, published by the National Bureau of Economic Research (NBER), explores the longer-term effects of this policy. They found that switching the curriculum’s language of instruction was associated with gaps in teacher preparation and available materials, which significantly affected students’ test scores and overall longer-term academic outcomes.
Yang and Lloyd leveraged the natural experiment created by the new policy: Unlike most studies focused on targeted preschool interventions, they were able to examine how a large-scale, nationwide, change in education quality during the early years of mainstream schooling plays out. The researchers exploited the linguistic composition of schools’ student body before the policy was implemented to predict which schools were most affected and to isolate the effect of the policy from potential selection bias.
Although the Philippines has 184 distinct spoken languages, before the policy was implemented, Tagalog and English were the primary languages of instruction in schools. When the policy rolled out, some schools chose to stick with Tagalog, forming the control group for the study. Other schools, however, switched to a language other than Tagalog, making them the treatment group. Specifically, they found that students in treatment schools experienced significant declines in their Grade 6 test scores across all subjects, and by 2020—eight years after the policy was implemented—completed one-third fewer years of schooling as compared to students who continued to receive education in Tagalog.
Students who attended schools with instruction in a new language experienced worse educational outcomes than their peers in schools with instruction in Tagalog. To explain this decline, the researchers point to the fact that, prior to the policy, teachers were trained in Tagalog and English, and classrooms were well-equipped with resources in those languages. The switch to a new language of instruction created disruption and was associated with implementation challenges, such as gaps in teacher preparation and available learning materials, ultimately impacting students’ success.
Their work highlights the importance of evaluating policies, particularly in early education. “From a policy standpoint, our study highlights the critical importance of maintaining and improving the quality of early education,” Yang and Lloyd write. “The substantial long-term costs associated with even temporary declines in educational quality suggest that policymakers should exercise extreme caution when implementing reforms that could potentially disrupt early learning environments.”
Read the full NBER working paper here>>
