@stray_dog_ I guess you were unlucky. Or your art teacher didn't know enough people. When I was taking art class, most of our nude models were young women. We had some old guy here and there but it mostly was women.
I think our teacher trick was to ask professional dancer. Mostly because he was asking them to old the same complicated af pose for 20 minutes straight without moving, and you'd be surprised at how hard it is. (We were doing nude model sketch by starting with 1-2 minutes poses to learn how to draw a fast outline, and finishing the session with 20 minutes poses to learn how to draw details and shadows)
Also dancers are used to being seen and people comes only for drawing seriously which helps.