The purpose of this pilot study was to examine the effects of improving a physical education teacher's content knowledge and, in turn, the teacher's instructional effectiveness and student learning in an upper elementary physical education setting. Four classes were randomly assigned to either a comparison condition (n[subscript 4th] = 9 students; n[subscript 5th] = 17) or an intervention condition (n[subscript 4th] = 7; n[subscript 5th] = 10). The teacher taught both conditions. The teacher first taught two classes in the comparison condition in a manner that he had taught for the past five years. Following the completion of the teaching, he received a content knowledge workshop. After the workshop, the teacher taught two classes in the intervention condition. Assessment of the teacher following the workshop showed that he obtained higher content knowledge scores than prior to the workshop. These improvements in content knowledge positively impacted his enacted teaching with more appropriate task selection and better instruction. Student learning also significantly improved in the intervention condition, not in the comparison condition, from pre- to posttest. The findings of this study extend the research demonstrating the effectiveness of improving the content knowledge of teachers in impacting student learning, in this case in the upper elementary grade band.