From left to right: Fukuoka (speaking), Kokedamura, the Vice Principal and Yamagata (being looked at by Mai)
A student with glassesYamagata sensei (teacher). In ep 2 asks to be called Kunio which may be his first name. Though he asks to call Mai as "Macchi" so this is unclear.
The principal is a man with glasses who appears via TV broadcast: Principal Kokedamura.