Περικοπεί θέα αρσενικό φοιτητής σκούπισμα μαθηματικές εξισώσεις με σφουγγάρι στην τάξη - Φωτογραφίες & Εικόνες Αρχείου

School board with inscriptions on it close-up

Teacher draw condition of phase synchronism

Student boy writing mathematical formula

Partial view of female teacher writing equation on green chalkboard

Male teacher wiping mathematical equations with sponge from chalkboard in classroom

Cropped view of female teacher with wooden pointer explaining mathematical equations in classroom

Male teacher in formal wear writing equation on chalkboard in maths class

Cropped view of female teacher holding wooden pointer on chalkboard background

Dissatisfied teacher looking at student who talking on smartphone in classroom

Pensive male teacher touching chin and solving equation on chalkboard in class

Male teacher in formal wear wiping mathematical equations with sponge in classroom

Teacher standing near chalkboard and speaking with student who talking on smartphone

Female professor pointing at chalkboard with equations during lesson