Answer:
National/ethnic identity is transmitted through education by many mechanisms, for example students singing the national anthem before school, or learning about world events from the perspective of their own nation/culture. Education is a tool to form functioning members of society, so that society will put many of their own ideals in their education system, in order to produce people that can function properly in that specific society.
This also functions to create a sort of 'collective identity' between members of that society, because all of them would tend to think the same way, for the most part.