The idea that girls are smarter than boys could come as a result of a 2015 study that says girls outperform boys in educational achievement in nearly 80 percent of countries. However, there is no scientific basis for this generalization, because there is no uniform way to measure intelligence.
Researchers at the University of Missouri and the University of Glasgow studied the educational achievements of 1.5 million students between 2000 and 2010. They discovered that girls outperformed boys in math, reading and science, regardless of gender issues present in their country.
In fact, the educational gap favored the girls even more in countries where women's rights are severely limited, such as Qatar and Jordan. The study concluded that political, social and economic gender inequality has no direct relation to educational performance. As of 2015, the reason that girls typically excel more in school is unknown.
However, there is no proof that educational ability is a reflection of intelligence. Female babies develop coordination earlier, and they are better listeners and speakers. They also make more eye contact, and they respond more to emotional and social stimulation. Boys are more active and awake as babies, and they develop an interest in systems and objects, rather than people.
Girls develop better vocabularies and excel more at language throughout their lives, but boys are better at mathematics and reasoning. The differences in brain development between the sexes are not considered to be proof that one sex is more intelligent than the other.