Nowadays, there are many thoughts, attitudes and movements related to signs of radicalism. This phenomena have the potential actions that strengthen intolerant actions or reinforce acts of terrorism in the name of religion. This study was conducted to answer two problems: typology of radicalism, and way of combating radicalism in students. The subjects of this study were school principals, Islamic Education teachers as school spiritual leaders, students, and educational communities related to student activities. Data of this study were collected by methods of observation, questionnaires and indepth interviews. The results show that typology of radicalization consisted of three phases: transformation (students receive and listen to explanations about radicalism), internalization (they believe and conceptualize the radical values into a value system), and characterization (the values of radicalism have already entered the students). Islamic teachers had a central role in combating the radicalism in students at school. Islamic teachers were not only those who taught the Islamic teaching in the class based on the written curriculum, but also those who educated Islamic values as the hidden curriculum as well as those related to students activities outside of school.