Hot sensei!
My two math tutors form high school were like in their early twenties when i was a sophomore. They were so good looking I would get good grades in Algebra only when they tutored me.
Also, my World History teacher (middle twenties) during 10thgrade too was very good looking. Actually, my best friend and I during senior year kind off hinted/told the teacher that we wanted to invite him as a date for prom

His face was priceless.
This chemistry teacher (late twenties) in college is the most good looking teacher i have had, he is tall, sarcastic, athletic, well built, nice ass, just hot