This action research study of teacher instructional planning and professional development was conducted using qualitative and quantitative data in the needs assessment, Iteration 1 and 2. The purpose of the needs assessment was to uncover teacher perspectives regarding instructional common planning time and unit planning and teacher behaviors at the building, department, and district level in order to inform the intervention iterations. Iteration 1 and 2 focused on determining if “Understanding by Design” (UbD) framework affected teacher unit planning instructional practices at the building level. The UbD framework was based on the Marzano Unit Planning Rubric and applicable checklist. Through the professional development intervention framework (Cooper, 2009), the coach-researcher worked alongside teachers in both iterations when developing a unit of study aligned to curriculum standards. Teachers in both iterations indicated the professional development intervention and the Understanding by Design framework positively influenced their unit planning instructional practices and transformed their planning thinking. The findings indicate the importance of understanding teacher instructional challenges to inform the improvement of instructional planning professional development. In addition, the findings suggest the Understanding by Design framework was an effective tool in improving teacher unit planning instructional practice at the building level.