Cooperating teachers and student teachers share a unique internship that allows the development of skills for both individuals. The literature states that cooperating teachers can grow from student teachers; however, there are a few sources that state the areas in which this growth occurs. The purpose of this study was to determine if growth or impact happened in the areas of instructional practices, coaching skills, and self-efficacy during the student teaching process. This mixed methods study included a survey, focus group interview, and single interviews to determine whether any change was made. The survey created descriptive statistics, a Pearson correlation test, and interviews to balance the quantitative and qualitative data. The findings revealed that student teachers had an impact on instructional practices within the survey, focus group, and interviews. Coaching skills and self-efficacy revealed the impact was subtle as it showed in the positive correlation. The significance of these was that teachers reflect more because of the student teacher process and thus become better teachers; this leads to higher student achievement. Cooperating teachers pass on their knowledge to student teachers and colleagues by working together in collaboration and teaming to do what is best for the students. [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.]