Instructional coaching has been a professional learning opportunity that many school districts have employed to support teacher practice. Pairing instructional coaching with on-going workshops is a relatively new approach to professional development. Participants for this study include fourteen middle school teachers that teach either mathematics or collaborate with special needs students. This study examines the effect that pairing instructional coaching with on-going workshops (with a primary focus on proportional reasoning) has on participants' content knowledge and their perceptions of coaching. Drawing on Wenger's community of practice theory and post-modern theory of power, this study employs mixed-methods design. Pre- and post-tests for proportional reasoning were administered to analyze the extent to which content knowledge changed over the course of the study. Pre- and post-interviews were conducted with each participant to determine any misconceptions each had on proportional reasoning and their perceptions of coaching (before and after the study's instructional coaching). Grounded theory and thematic analysis was employed on the pre-and post-interviews to examine the role that power played in the participants' perceptions of effective coaching attributes. Results suggest that (a) instructional coaching coupled with on-going professional workshops can change content knowledge in participants; (b) perceptions of coaching can change as the result of experiencing a coaching relationship and (c) power dynamics in the coaching experience determine the extent to which participants see the effectiveness of coaching as a professional development activity. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]