Senior professor in glasses and formal suit pointing at blackboard and writing with chalk while giving lecture in college
Senior professor pointing at formulas on chalkboard and explaining them to group of college students while giving lecture
African American professor pointing at graphs and formulas on blackboard and speaking to students while giving math lesson in university
Man in his 40s giving a lecture on organic chemistry pointing to a formula on a blackboard in a high school or college classroom
Medium slowmo of contemporary male mid-adult teacher sitting by desk and giving online Maths lesson on laptop pointing at blackboard with geometry problems
Senior professor writing with chalk on blackboard and talking to students while giving lecture in college
Medium slowmo of university professor explaining new material to diverse students in lecture hall
Handheld shot of middle aged university professor pointing at blackboard when asking question to student during lecture
Senior Caucasian male professor at military academy in formalwear pointing at tactical vest on one of recruits while giving lecture to students in classroom
Close up view of senior professor using chalk while writing on blackboard and giving lecture in college
Lecture hall is full with medical students, professor is giving a lecture.
Rear-view medium slowmo of group of multiethnic university students entering big lecture hall while male mid-adult professor writing topic of lesson on blackboard