This study aimed to determine the teachers' choices of instructional materials in teaching English at elementary schools. The reasons behind preferring or not preferring some certain instructional materials specified within the research were analysed. To this end, during the course of School Experience, 68 prospective English teachers observed 38 teachers of English working at 14 elementary schools on a weekly basis, and they completed a questionnaire. A semi-structured interview was also conducted with five randomly selected teachers to identify their reasons for choosing certain instructional materials. The descriptive results revealed that most of the teachers were reluctant to use many of the highly beneficial materials due to reasons including overcrowded classes, limited technological knowledge, lack of time for preparation, curricular time constraints, heavy work load, burnout etc. The study suggests that apart from course-books teachers should be encouraged to use other instructional materials to motivate learners and offer an interactive foreign language teaching atmosphere.