Download: Why are girls performing better than boys in school?
Research found girls have been performing better than boys in school for nearly a century, according to the American Psychological Association.
An analysis used more than 308 studies from 30 countries involving more than a million students.
Seventy percent of those students were from the United States.
The authors concluded parents may assume boys are better at math and science so they encourage girls more.
They also noted girls typically study to understand the material, while boys often work just to make the grade.