Professor segurando giz perto de câmera digital borrada e quadro-negro na classe - Banco de fotos e imagens

Tutor pointing at chalkboard and holding digital tablet near camera in school

Cheerful teacher holding chalk near chalkboard and digital camera in classroom

Teacher in eyeglasses talking near blurred digital camera and chalkboard

Teacher talking near blurred digital camera and chalkboard with math formulas in classroom

Teacher holding chalk and talking near chalkboard with formulas and digital camera

Teacher talking near digital camera and chalkboard with math formulas in class

Teacher in eyeglasses explaining math formulas on chalkboard near digital camera in class

Smiling teacher holding chalk near chalkboard with formulas and digital camera

Teacher talking near math formulas on chalkboard and blurred digital camera in classroom

Teacher talking near math formulas on chalkboard and digital camera in class

Shocked geometry teacher touching face and pointing with finger at chalkboard with illustration

Smiling teacher looking away and pointing with finger near chalkboard

Brunette doctor in white coat writing chemical formulas on glass board in lab

Low angle view of blurred chemist holding clipboard and felt pen near chemical formulas on glass board

Shocked teacher touching face and pointing with finger near chalkboard

Blurred doctor with felt pen and clipboard writing chemical formulas on glass board

Low angle view of scientist with felt pen near blurred formulas on glass board

Thoughtful teacher touching head and looking away while standing with hand on hip near chalkboard