While school enrollment at the primary level has been rising in developing countries rapidly, international measures of education quality do not exhibit a parallel improvement. Since parents' expenditure is an important determinant of children's school performance, we investigate parents' investments on quality measured by their spending on books and other school materials. We develop an overlapping generations model in which parents use children's human capital as a screening measure for adjusting their investment. Our main hypothesis is that families consider better school performance to be a reliable predictor of future return, and this will incentivize them to invest more.