Teacher Input Non-Fungibility
Providing fungible material grants leads to severe household expenditure substitution and zero net learning gains, leaving governments uncertain about which school inputs reliably increase learning over multi-year horizons.
Picture this
Unlike books or pencils, highly specialized human inputs—such as additional classroom teachers or structured student tracking—cannot be easily purchased or replicated by individual parents at home. Providing an extra teacher is like expanding a municipal power grid: individual households cannot build their own neighborhood power plant, so the public addition directly expands total capacity without private offset.
What the evidence says
Extra contract teacher provision yielded persistent learning gains over two years where two-year cumulative test score gains were twice as large as single-year gains (p < 0.01), contrasting with material block grants where Year 2 gains fell to 0.02 SD.
- Who
- Representative sample of government primary schools in rural Andhra Pradesh, India across 500 evaluation schools.
- How
- Multi-year randomized controlled trial comparing material block grants ($3/student) against extra contract teacher allocations over two academic years.
What to do
Direct public education investments toward high-skill human capital and structural classroom organization rather than easily substitutable consumer materials.
From the source
"In a parallel experiment on the provision of an extra contract teacher to randomly selected schools in Andhra Pradesh... the impact of the extra teacher was identical in both the first and second year of the project, suggesting that teacher inputs were less likely to be substituted away."
School Inputs, Household Substitution, and Test Scores