The images or social representations of current high school students are connected with the information they receive from their teachers at school, then to know the meanings of their conceptions, can help to improve the practice of Didactic in the process of teaching-learning. The aim of this research was to interpret the significations of teaching in Mexican high school students on a Chemistry course with the Theory and technique of Natural Semantic Networks (NSN). The method used for the study was research-action with a critical interpretative focus, the design of the research was cross-sectional. The population of this study was formed by 79 students officially enrolled into the UCEM (Precollege Institute of the Center of Mexico) educational system. Results have shown that students represent teaching with the meanings of: learning (semantic weight= 194) and teacher (172), despite of these meanings, it exists other words inside the SAM (Semantic Association Memory) group like values (32) and livres (161). In conclusion of this research it can be said that current social images are built with the categories of learning like a process included on teaching and professor like actor of the educational phenomenon.