This document outlines the goals and plans for a professional development session on teaching addition and subtraction. It aims to improve student enjoyment and achievement in math by increasing the use of concrete materials, familiarity with skill progressions, setting open-ended problems, and using online resources. The PD will investigate mental and written addition/subtraction concepts using concrete materials and rich tasks. References and an agenda are provided, with the agenda including open tasks, strategies, and summaries of effective teaching based on research emphasizing modeling, context, flexibility, and place value understanding.