Sites that feature material related to the teaching of black hole physics, such as course syllabuses, ideas for class activities and "teacher's kits".
If the focus of a website is on how to teach (how to design a course, what classroom activities to include), it should go in this category. If the focus is on the subject (for instance, lecture notes giving a general introduction to the subject of black holes), they should go in the parent category Black_Holes.