In this paper we try to answer why some subjects taught in school are considered controversial by certain people, and how teachers can deal with conflicts related to these that may arise in the classroom. Our literature study emanates from four different scientific subjects; evolution, climate change, vaccination and sexual education. The information used in the paper was found and chosen through various search engines using words correlating to our four subjects, and primarily consists of peer reviewed articles. Furthermore, we made the decision to only search for articles written within the last decade, since we wanted the study to be relevant and up to date. Using the information, we then proceed to research each of the four subjects, and present our findings in the results. We try to conclude similarities and differences between the various subjects in the discussion. Our study found that the people opposed to the teaching of these subjects were mainly religious individuals, and the main reason for the opposition was either a contradiction between science and their faith, or fear. Climate change was a divergent subject where the causes for disbelief were found to often be economic or political. We found various ways to handle disputes in the classroom, which differed for each subject. The common denominator however, was to always treat parents and students with respect, trying to understand their point of view, and meeting their arguments with science linked to the curriculum. We found this paper to be highly important for our future understanding of the complexities and importance of the conflicts between religion and science, and it will help us in our future profession.