The purpose of this study was to investigate the challenges and prospects of teaching in largernclasses of secondary schools of west Hararghe zone. Though many research conducted in largernclass and its challenge encountered, they all limited to some specific areas. Since the area forrnthis study is different from the area studied before in different situation like environment, custom,rneconomic and way of living, conducting this research was important and timely. To, con:!u~!thiSrnresearch, descriptive survey method was employed. The primary sources of data werern165teachers, 400 students of secondary school (9-10) and 10 principals, vice-principals andrnschool supervisors. Purposive sampling, simple random sampling and stratified randomrnsampling techniques were employed to select secondary schools, teachers and studentsrnrespectively. QU!!Eionnaires were the main data gathering instruments while interview,rnobservation and document analysis were employed to enrich the data gathered throughrnquestionnaires. Likewise, the collected data were analyzed quantitatively using percentage andrnmean values, and qualitatively by using descriptive narration. The finding of the study mirrorsrnthat, on average, the number of students accommodated in a section was 80 and above which isrnrelatively very large. There was an implementation bott~eneck with respect to methods ofrnteaching used in large classes. Most frequently teachers utilized lecture method of teaching inrnthese classes. Disciplinary problems, lack of communication, lack of effective assessment andrn....:--rnfeedback, class involvement and inability to identify students need and behaviors.'> by teachersrnwere problems observed in large classes. Majority of the teachers teaching in the large classesrnwere not acquainted with the know-how of teaching large classes. Besides, they didn't get initialrnand on-job trainings on how to teach large classes and the support provided to them by thernprincipals and school supervisors were not sufficient. Qn top of these, educational facilities /rnmaterial including textbooks were not sufficient enough to materialize effective teachinglearningrnproc~ss in large classes. Finally, necessary recommendations regarding teachers loadrnand training, leaching method (promoting active learning) deeper understanding of callses andrn/"rntypes of conflict with careful planning and implementing it for classroom management, teachingrnmethods that increase students involvement, text books and the neces ary materials, andrnprofessional support given by principals and supervisors were given for improving thernchallenges of teaching in large classes of secondary school