The Opportunity Cost of School Time: Effects of Intensive Violin Instruction on Academic Performance in Grades One and Two

This communication examines the impact of a music education program on the academic progress of disadvantaged students aged 4 to 8. The program integrates three violin lessons per week into the regular school schedule over a four-year period. It is based on the widely held — though inconsistently supported by scientific evidence — belief that learning a musical instrument enhances general cognitive abilities.

This presentation draws on findings from a four-year quasi-experimental design involving 2,000 children across 60 schools. Using propensity score matching and linear regression analyses, we identified a small positive effect on academic performance toward the end of preschool. However, this effect reversed in the first and second grades, showing a significant negative impact on language skills (reaching d=-0.132, p<0.01 by the end of grade 2) and no measurable effect on math skills. Notably, the decline in language performance disproportionately affected students from lower socioeconomic backgrounds, revealing an anti-socially redistributive trend.

These results raise a larger question that is little addressed: the opportunity cost of school time allocation. Indeed, most impact evaluations tend to focus on the direct benefits of educational interventions — such as measuring progress in math after a math-related program — without considering potential adverse effects on other subjects that lose instructional time as a consequence. Our findings suggest that the growing demands placed on school (such as providing health prevention, media literacy, environmental education, etc.) may undermine foundational learning if overall instructional time is not increased. Furthermore, as demonstrated in previous research, the most vulnerable students are the most sensitive to changes in school time allocation, as they have fewer opportunities to recover lost learning outside the classroom. While these additional curricular elements are valuable, they may crowd out subjects like language and math, ultimately exacerbating social inequalities.