The evolutionary theory is considered one of main axes of biology. However, its teaching faces many difficulties in several countries. In Brazil, the resistance to evolutionary theory is more common among Pentecostal and neo-Pentecostal, religious groups that have strongly grown over the past decades. In this study, we investigated the teaching of evolution in two schools in the state of Rio de Janeiro. We performed observations over nine months in classes of the first year of high school, interviews with teachers and students and applied a questionnaire to latter. The results indicate great complexity and diversity in relation to the concepts of creationism and evolution among teachers and students, even among the Pentecostal and neo-Pentecostal. Few conflicts were observed in the classroom, but they were expressed in the interviews and questionnaires. Quantitative data indicate that Pentecostal and Neo-Pentecostal students tend to accept more the biblical account of the origin of living beings and have greater religiosity rates than other religious groups. We conclude that more research on this topic in biology classes are essential to develop teaching strategies aimed at understanding the evolutionary theory.