We find robust evidence that exposure to teacher collective bargaining laws worsens the future labor market outcomes of men: living in a state that has a duty-to-bargain law for all 12 grade-school years reduces male earnings by $1,493 (or 2.75%) per year and decreases hours worked by 0.52 hours per week. Estimates for women do not show consistent evidence of negative effects on these outcomes. The earnings estimates for men indicate that teacher collective bargaining reduces earnings by $149.6 billion in the US annually. Among men, we also find evidence of lower employment rates, which is driven by lower labor force participation. Exposure to collective bargaining laws leads to reductions in the skill levels of the occupations into which male workers sort as well. Effects are largest among black and Hispanic men, although white and Asian men also experience sizable negative impacts of collective bargaining exposure. Using data from the 1979 National Longitudinal Survey of Youth, we demonstrate that collective bargaining law exposure leads to reductions in measured cognitive and non-cognitive skills among young adults, and these effects are larger for men.