The problems in this study are: knowing the strength of the relationship between the principal's academic supervision of teacher professional competence, the strength of the relationship between teacher professional competence and student cognitive learning achievement, the strength of the relationship between principal supervision in improving teacher professional competence and student cognitive learning achievement in Gugus Ki Hajar Dewantara Koorwilcam Dindikbud Pengadegan Purbalingga.
The purpose of this study was to analyze the strength of relationship of 1) principals' academic supervision on teachers' professional competence, 2) teachers' professional competence on students' cognitive learning achievement, 3) principals' academic supervision on teachers' professional competence and students' cognitive learning achievement,
The population in this study amounted to 11 principals, 66 classroom teachers and 989 students. The sampling technique of this research is using nonprobability sampling with purposive sampling technique. So that the sample of this study were 11 principals, 11 grade VI teachers and 112 grade VI students.
The method used for data collection was the questionnaire method. The data analysis used was quantitative descriptive analysis, contingency correlation test to determine the effectiveness of principals' academic supervision on teachers' professional competence and cognitive learning achievement in Gugus Ki Hajar Dewantara Koorwilcam Dindikbud Pengadegan.
The results showed that the principal's academic supervision had a strong relationship with teacher professional competence with a contingency coefficient of 0.716 and the relationship level reached 87.7%. Teachers' professional competence variable has a very strong relationship to students' cognitive learning achievement, with a contingency coefficient of 0.722 and the relationship level reaching 88.5%. Intensive academic supervision of school principals can have a positive impact on improving teacher professional competence, and teacher professional competence has an effective force in improving students' cognitive learning achievement.