The following document represents a Problem Based Learning Project (PBL) focusing on school leadership practices leading to increased student achievement. Current research findings indicate effective principals recognize the importance of building teacher capacity through promoting collaborative team work. School principals effectively leading Instructional Data Teams (IDT) ensure teachers are actively engaged in the learning process, are challenging low expectations, and work collaboratively to improve teaching and learning. Therefore, the problem is the perceived lack of principal's knowledge and support of developing teachers' professional capital to improve teaching through data driven teamwork. This project has been driven by three guiding questions: (1) Do principals have the knowledge base and understanding of how IDT can build capacity and influence teacher behaviors?; (2) Do principals understand their role in leading and implementing IDT?; and (3) What critical actions have principals implemented to establish effective IDTs? Through this evaluation, common themes emerged and the team identified several issues impacting school districts. These included, methods for meeting increasing accountability measures, techniques for improving student achievement, effective professional development of teachers and staff, data-driven decision making, building leadership capacity among staff members, leadership of effective teamwork within schools, leading professional learning communities, and leadership of collaborative Instructional Data Teams. The team analyzed current literature related to leading effective Instructional Data Teams and conducted interviews of elementary principals from high performing elementary schools located in the Kansas City Regional Professional Development Center. The project team conducted a qualitative analysis of the perceptual data gathered from the principal interviews, identified emergent themes, and compared the emergent themes with best practices identified by the literature. The team analyzed the emergent theme data and used this analysis to answer the project's guiding questions and provide recommendations to the field of education. The project team concluded principals have varying degrees of knowledge related to leading Instructional Data Teams. This analysis led to recommendations for principals, superintendents, boards of education, institutions of higher learning, and state departments of education related to leading and implementing effective Instructional Data Teams. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]