Purpose: Existing research suggests that organizational learning, jointly implemented by principals and teachers may reduce agency risks and improve school management effectiveness. However, research investigating how this process occurs is lacking. The relationship between school leaders promoting the involvement of teachers in school-wide processes focused on instructional improvement and the coherence characterizing a school's instructional program remains unclear. Design/methodology/approach: The authors identified shared instructional leadership and instructional coherence, as two key variables describing the process of organizational learning and the outcome of agency risk reduction. The authors employed hierarchical linear modeling to test the hypothesis that shared leaderships positively predicts differences among schools in instructional coherence. Findings: Based on a sample of 113 public high schools selected from a U.S. Midwestern state, the results confirm the hypothesis. Research limitations/implications: This study uses the existing theoretical and empirical findings to interpret the potential relationship between shared leadership and instructional coherence, and validates it through empirical data analysis. The findings expand the understanding of the shared leadership theory. Although the design of this study is strictly based on theoretical and empirical findings, and part of the purpose of the research is to find the reasons why shared leadership seems to be insignificant in some countries and regions, readers should still note that the sample source is American schools. The findings of this study are worth examining with different samples in future studies. Practical implications: Since the direct relationship between shared leadership and student standardized test scores has been difficult to measure, and in some countries even negative, there is debate about the need for shared leadership. The difficulty of measurement is caused by the diversity of leadership subjects and the complexity of leadership tasks. This study finds out the direct object of shared leadership and the process of exerting its effects, which will expand the understanding of the positive meaning of shared leadership. This will help different countries and regions better identify and play the role of shared leadership. Originality/value: Based on the combination of organizational learning theory, agency theory and shared leadership theory, the study modeled the process of collaborative organizational learning among principals and teachers. The study employed instructional coherence as a form of structured organizational learning that is a prerequisite for improvement in common measures of student learning such as standardized test scores. Do so provide practical guidance for educators seeking improvement through organizational learning.