Some countries have single-sex education models, while in others both single sex and mixed schools co-exist and it is up to the parents or the children to decide which model is preferable. Some educationalists think it is more effective to educate boys and girls in single-sex schools because they believe this environment reduces distractions and encourages pupils to concentrate on their studies. This is probably true to some extent. It also allows more equality among pupils and gives more opportunity to all those at the school to choose subjects more freely without gender prejudice. For example, a much higher proportion of girls study science to a high level when they attend girls' schools than their counterparts in mixed schools do. Similarly, boys in single-sex schools are more likely to take cookery classes and to study languages, which are often thought of as traditional subjects for girls.