Tuesday is International Women's Day, an event observed worldwide to recognize the important role women play in society. In honor of the day, UNESCO, a United Nations agency that promotes cultural and educational reform, has issued a report that highlights the subtle — and sometimes not-so-subtle — sexism on display in textbooks designed to educate children around the world.

In the article, published by UNESCO's Global Education Monitoring Report, Aaron Benavot and Catherine Jere of the University of East Anglia in Britain write that women are dramatically underrepresented in textbooks worldwide. Even when featured, the authors say, women are often shown conforming to stereotypical gender roles such as a homemaker or teacher, while men were often presented in leadership roles.

The sexism appears remarkably widespread all around the world. The authors cite studies that show that just one-fifth of characters in Chinese history books are female and that they "appeared dull and lifeless in comparison with the more vibrant males." In Indian textbooks, more than half of the illustrations showed male-only groups; just 6 percent showed all-female groups. Another study showed that only 30 percent of the characters featured in textbooks in Cameroon, Cote d’Ivoire, Togo and Tunisia in the late 2000s were female, while the proportion in a textbook published by Iran's Education Ministry in 2012 was just 20 percent.

Even in rich nations such as Australia, the gap is clearly illustrated by school textbooks — men not only made up the majority of characters in Australian textbooks, UNESCO's report found, but also featured in more than twice the number of law-and-order roles as women and four times the number of roles in politics and government.

The Global Education Monitoring Report is asking people worldwide to share images from textbooks on Twitter and Instagram, using the hashtag: #BetweenTheLines.

Judging by previous displays on social media, there is certainly a wealth of material out there:

The problem is certainly not new. In fact, as far back as 1986, UNESCO was publishing studies that detailed the "sexist prejudice and stereotypes that abound in the texts and pictures of [children's school] books" and suggested ways to combat them. However, the casual sexism in textbooks designed for children seems to have lingered in much of the world.

Benavot and Jere suggest that this is attributable to a variety of factors, including a lack of national and local support for recommendations made at an international level. On the bright side, there has been a notable change in some countries, the authors say. Some textbooks in India and Malawi are asking students to identify their own gender biases.

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