The secondary school graduation rate for boys is lower in Quebec than in any other Canadian province. Since education brings many benefits, both individually and socially, this under-schooling of boys is a cause of concern. In this report, we seek to quantify the benefits of boys catching up with girls in terms of graduation rates. To do this, we use data from the Canadian Census of Population, which we analyse to achieve three interrelated objectives. First, we decompose the gender gap. Second, we look at how employment earnings, taxes paid and government transfers might vary in three counterfactual scenarios where men catch up with women in terms of high school graduation. Finally, we propose a series of projections from 2021 to 2066 that seek to evaluate the workforce by educational attainment and the gains in employment income if the high school graduation rate for boys equalled the high school graduation rate for girls. These calculations make it possible to assess the socio-economic benefits of such a catch-up, which is an essential element of any benefit-cost analysis.