The idea of the study is that the value potential of the subject is a fundamental element of the knowledge system as part of the realization of the idea of sustainable development in education. The basis of the study used the classification of value categories proposed by Milton Rokeach in 1979. We found that in the main school, the content of the subject “Biology” is primarily aimed at forming ideas about terminal values – “life”, “health”, “nature”; in high school – about terminal values “life”, “health”, as well as instrumental values – “perseverance”. The value ideas of a biology teacher are one of the key factors in the formation of students’ value ideas. In the structure of value representations of biology teachers, the three leaders are orientations towards terminal values. We have put forward the assumption that there is a dissonance between the value ideas of respondents and the values that the school biology course is aimed at forming an idea about.