The purpose of this study was to obtain the perceptions of cooperating teachers in beginning and middle school instrumental music regarding their student teachers' skills and knowledge both at the beginning and at the end of the student teaching experience. The related research has focused primarily on two areas of music teacher education. Program evaluation research has attempted to determine the competencies that are essential for teaching music, as well as the level of success of college and university music teacher education programs in teaching these competencies. Other research has focused on the student teaching experience itself and the relationships that form between cooperating teachers and their student teachers. A survey study was designed and a questionnaire created. Essential skills and knowledge (competencies) identified in the related research provided the basis for the questionnaire. Items were included based on relevance to beginning and middle school instrumental music students. Due to the importance of instrumental pedagogy in teaching these students, a section dealing specifically with pedagogical competencies was added to the questionnaire. The population for the study was identified as all cooperating teachers who had observed student teachers assigned to them by Ohio colleges and universities in beginning and middle school instrumental music classrooms within the last three calendar years (spring, 2009, to spring, 2012). Sampling was conducted by contacting representatives from music education departments at 16 Ohio colleges and universities and asking for names of cooperating teachers with whom they had placed their student teachers. A list of 119 cooperating teachers was assembled from the information provided, and questionnaires were mailed out to the potential respondents. A total of 73 questionnaires were returned, representing a 61.3% response rate. Sixty-three of the questionnaires were determined to be useable. A combination of descriptive and inferential statistics was used to examine the data. Descriptive statistical analyses primarily involved comparing means within the sample and examining trends in the data. Inferential statistics involved the use of Pearson product moment correlations (with tests for significance), t-tests, and analyses of variance. The data showed that cooperating teachers perceive their student teachers to be strong in personal/professional competencies and weak in competencies related to teaching. Musical competencies were rated in the middle. Student teachers were perceived to have improved significantly on nearly all competencies during their student teaching experiences, but they improved most on the teaching competencies. The smallest improvements were perceived on the personal/professional competencies. Pedagogical skills and knowledge were an area of concern for the cooperating teachers, although student teachers were usually able to teach the fundamentals associated with their primary instruments and instruments from the same family. An examination of demographic variables revealed significant differences between cooperating teachers on their perceptions regarding certain competencies. The variables that showed significant differences were: the duration of the student teaching experience, the grade levels taught by the cooperating teachers, the education level of the cooperating teachers, whether the teachers taught private lessons, and gender. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]