During the 2006-2007 school year, the Theoretical Learning approach is being partially used to enrich mathematics instruction in selected Grade 3 classrooms (at Hall, Lyseth, and Presumpscot), to consolidate the children's concept of multidigit number and to provide a good transition to traditional approaches. In these classrooms, the approach to addition and subtraction of multidigit numbers continues to be enriched by techniques developed in the Theoretical Learning program.