Προσωπογραφία μεσήλικα μαθηματικός χαμογελώντας ενώ βλέπουν τα φωτογραφικών μηχανών κατά greenboard στην τάξη - Φωτογραφίες & Εικόνες Αρχείου

Portrait of a dedicated Maths teacher explaining a theory against greenboard during class in a modern school or university

Maths teacher standing in front of a blackboard with equations holding a tablet and looking to the side with a serious expectant expression

Male teacher writing a mathematical equation on a blackboard in a classroom while holding a tablet-pc

Relaxed confident male teacher standing leaning against a blank green chalkboard in the classroom with folded arms

Grey hair professor looking at students rising hands

Happy satisfied male teacher standing with his hands behind his back and a pleased smile against a blank green blackboard

Nice teacher smiling at camera in his classroom

Portrait of happy male professor with arms crossed sitting on desk in classroom

Male teacher taking question in class pointing with his pen with look of concentration

Male teacher taking a question from the class as he stands in front of a blank chalk board extending his hand

Friendly male teacher teaching form a set of class notes standing in front of a blank green blackboard with copyspace

Male teacher taking question in class pointing with his pen with look of concentration

Portrait of teacher standing in front of a blackboard

Friendly confident post graduate student standing clutching a folder of class notes with his back to a blank blackboard with copy space