Even before the war was over and the Dark Lord was placed in absolute power, there had been small schools around the country preparing young witches and wizards for Hogwarts. These primaries instructed their students in all of the basic subjects they needed a foundation in before they could hope to learn magic at age eleven. Compulsory attendance at Hogwarts had been mandated early on once the war ended. Even Muggle-born students were allowed to attend the school under very strict guidelines.