The differences in the depiction of boys and girls engagement in scientific activities in Adam's 6th grade science textbook, where three-fourth of the pictures are of boys and one-fourth of the pictures are of girls, is an example of INSTITUTIONAL SEXISM. Institutional sexism occurs when an organization is made up of people who share the same attitudes of being prejudiced against one sex (usually women) in a given situation, even though the organization’s policy may not be sexist in nature.