Noordhoff, the Netherlands' largest publisher of school textbooks, is planning to feature gay and lesbian couples in the assignments, questions and examples it uses in its teaching material.

In a radio interview, the firm's publishing director Frans Grijzenhout explained that while children have been taught about homosexuality in subjects such as biology and history for some time, the family situations presented in general teaching materials have always focused on mothers and fathers. He says it could now soon be same-sex couples doing the shopping in the examples presented to arithmetic pupils.

Mr Grijzenhout compares the development to the introduction of people from different ethnic backgrounds in school textbooks. The publisher argues that it is very important for school materials to reflect all aspects of Dutch society and to present homosexuality to children in a way that is natural and recognisable.

It will be a few years before gay and lesbian couples make their print debut, but they will be introduced more quickly in electronic material. The publisher notes that while teaching materials in the Netherlands are subject to government supervision, publishers have a relatively high degree of freedom in determining the content of their books.