The purpose of this study was to determine the effect of using concept mapping to promote reflective instructional decision-making among junior level education preservice teachers when planning lessons for elementary and secondary students. The researchers were interested in determining if there was a connection between the use of concept mapping to help preservice teachers improve their instructional decisions when planning lessons and their reflective practices when striving to improve the quality of their lessons. The eighty-five participants in the study were junior education majors enrolled in an introductory education course (Planning and Teaching Strategies for Effective Classroom Practice). This course provided opportunities for reflection of classroom practices, curriculum design and planning. The intervention group consisted of forty-one (n = 41) preservice teachers and the control group consisted of forty-four (n = 44) preservice teachers.