Add+VantageMR ® Course 1: In this 4-day (in-person) workshop, attendees will use diagnostic assessments and learning trajectories to guide the teaching of whole number topics. During this practice-based professional development, participants begin working with students to develop their knowledge and skills for day-to-day practice. The course focuses on foundational learning of whole number topics such as number words and numerals, structuring numbers, addition and subtraction, and topics that affect the development of future mathematical understanding.