ABSTRACT
The Additive level of the OGAP Addition Progression includes algorithms and strategies that are accurate, efficient, and generalizable and are built upon a solid understanding of number, properties, and relationships. There are three main types of strategies for multi-digit addition: decomposing and recomposing by place value; incrementing; and changing one or both numbers and compensating. Students should have opportunities to develop and use all three types of strategies so that they can deepen their understanding of number and approach problems with flexibility. The Traditional US and Partial Sums algorithms are more formalized ways to perform and record a decomposing and recomposing strategy, and it is important for students to see these connections. Students should have experiences developing and using strategies based on understanding of place value and properties of addition before they are introduced to standard algorithms in later grades. The chapter includes a vignette of a teacher’s adaptation of curriculum materials to provide math instruction that is aligned to the OGAP Addition Progression and the grade level Common Core expectations.
