Evolution is one of the most difficult and controversial topics. Scientific knowledge of evolution should belong to general knowledge of people, it should be the part of their natural science knowledge or biological education because it is the basis for accepting or refusing of other important topics such as genetical modification, global climatic change and others. Our aim was to analyse the inclusion of evolution in the teaching process in Slovakia in the subjects of history and biology and the associated potential threats to the formation of misconceptions. We measured the level of knowledge and understanding of evolution and evolutionary processes among high school graduates (N = 200). In doing so, we hypothesized that graduating high school students who have received evolutionary education achieve higher levels of both knowledge and understanding of evolutionary processes compared to those who have not received such education. We hypothesized that interest in science and acceptance of evolution would also positively influence levels of knowledge about evolutionary phenomena and understanding of evolutionary processes. Having used research, we claimed the impact of interest in natural science. We suggest to include the evolution as a main topic of biology into education through exploration-oriented teaching.