# Number and Operation in Base Ten

## Narrative for (NBT) Number and Operations in Base Ten

At Grade 3, the major focus is multiplication, so students’ work with addition and subtraction is limited to maintenance of fluency within 1000 for some students and building fluency to within 1000 for others.  They achieve fluency with strategies and algorithms that are based on place value, properties of operations, and/or the relationship between addition and subtraction. Such fluency can serve as preparation for learning standard algorithms in Grade 4, if the computational methods used can be connected with those algorithms.

For students in grade 3, the special role of 10 in the base-ten system is important in understanding multiplication of one-digit numbers with multiples of 10. For example, the product of 3 x 50 can be represented as 3 groups of 5 tens, which is 15 tens, which is 150.

## Calculation Method for Domains

Domains are larger groups of related standards. The Domain Grade is a calculation of all the related standards. Click on the standard name below each Domain to access the learning targets and rubrics/ proficiency scales for individual standards within the domain.