Methodology Da`wah (Islam) 22 Islam 20 Religious aspects 14 Study and teaching (Secondary) 12 Research 9 Arabic language 8 English language 8 Foreign speakers 8 Study and teaching 8 Missions 7 Study and teaching (Primary) 6 Project management 5 Teaching 5 Training of 5 Bibliography 4 Computer-assisted instruction 4 Evaluation 4 Management 4 Medical care 4 Motion pictures 4 Science 4 Ability testing 3 Aids and devices 3 Analysis 3 Communication 3 Da'wah (Islam) 3 Educational technology 3 Group work in education 3 High school students 3