Ένας μαθητής χρησιμοποίησε άσπρη κιμωλία για να γράψει μαθηματικούς τύπους στον πίνακα.. - Φωτογραφίες & Εικόνες Αρχείου

A smart young man solves a math problem with his back to the camera writing on a College blackboard.

Happy child child standing at the blackboard in the school class at the lesson

Student boy writing mathematical formula

High school student write on blackboard

Soft focus blue Chalkboard or green board. High School Student of Hand holding white chalk writing on green board in classroom .Education concept.

Soft focus blue Chalkboard or green board. High School Student of Hand holding white chalk writing on green board in classroom .Education concept.

Maths formulas written by white chalk on the chalkboard background

School children in a science class with a molecular model. Background image with soft focus. Education concept.

Soft focus blue Chalkboard or green board. High School Student of Hand holding white chalk writing on green board in classroom .Education concept.

Maths formulas written by white chalk on the chalkboard background

Plastic molecular educational model. On the background of the school board.

Plastic molecular educational model. On the background of the school board.