Hanzou
Grandmaster
Must teachers are not fit enough to go toe to toe with a teenager. Being older and out of shape puts them at a big disadvantage. Self defense for nost of them will need to be more preventive. Maybe educate teens at an early age about the law. Some teens do things because they know they are under 18. They don't have a good understanding of the exception that would make it legal for an adult to hit a teen.
Most? I’d say the vast majority. I would recommend every teacher to learn self defense of some type, regardless of what school they’re teaching at. We had a teacher train at my old gym years ago, and learning grappling saved her life. She got trained in how to grapple with teens because she actually grappled with teens of different sizes and power during training.
By the time of her attack, she was a very solid blue belt who was very good at escaping holds and pins, and exceptional at back takes.