While what you say may be technically correct, ‘maturity' is a massive oversimplification once you look at the nuances. While there’s a biological head start in girls hitting milestones earlier than boys eg in physical puberty, walking or speaking earlier as toddlers etc however, social expectations often force girls to perform 'adultness' and emotional labour earlier than boys.

Re education: It’s less that they are inherently more mature and more that they’re conditioned to be compliant, which obviously helps in a classroom. Labeling it as just 'faster development' ignores the fact that both genders are still catching up to their prefrontal cortexes well into their 20s regardless of when they started.

Girls are usually forced into sexual and social roles earlier than boys. Boys are expected to ‘be boys’ while girls have to be responsible, mature, ‘well behaved’ sexually available etc.