The purposes of this study were to explore the nature of the teaching-learning process in line with active learning methods and to identify the major challenges hindering the implementation of these approaches in mathematics classes. Both qualitative and quantitative methods of data collection were employed which is a mixed method research design. Probability proportional sampling technique for students and availability sampling technique for teachers were used. 25 mathematics teachers and 369 students were involved in the study. Questionnaires, lesson observation, and focus groups discussion were the data gathering instruments. The quantitative data obtained were analyzed using SPSS. The qualitative data were analyzed by narrating the information obtained from the data. Questioning method, group work, gap lecture, cooperative learning, and individual work were the methods used commonly by the teachers. Large class size; the amount of content to be covered; lack of instructional materials; lack of administrative support; and that it took too much effort from teachers are main challenges that hinder the application of active learning methods in the classrooms.
Key words: Active learning, challenges of active learning, constructivism, student centered.