In the US boys outperform girls in math. But we’re an outlier. As a Slate article describes it:
The only countries with a wider gap favoring boys are Colombia and Liechtenstein. Many Middle Eastern countries—notably Qatar, Jordan, and the U.A.E.—report a significant gender gap in favor of girls (though lower math scores overall). In Hong Kong, Singapore, and South Korea, the gender gap is miniscule, and the math scores are high. Shanghai registers no gender gap between boys and girls—together, they’re outperforming other teenagers across the globe.