Professeur masculin regardant le tube à essai tout en portant des lunettes de protection au bureau en classe - Photo & image de stock

Laughing middle-aged male science teacher holding up a test tube with forceps to show his class the chemical reaction taking place

Senior male teacher solving sums on blackboard with students in foreground at classroom

Portrait of male teacher checking examination papers at bench in classroom

Male teacher writes on blackboard with a chalk

Young boy watching a chemical reaction standing wearing safety goggles and a lab coat and holding up a glass test tube

Mature male teacher writing on chalkboard in classroom

Thinking male teacher at bench in classroom

Senior male teacher teaching mathematics while pointing at blackboard in classroom

Mature male teacher holding paper while writing on chalkboard in classroom

Student hands writing structural formula on the blackboard