In Grade 3, students build fluency with adding and subtracting within 1000, using strategies based on place value, properties of operations, and the relationship between addition and subtraction, building on strategies learned in second grade for adding within 100 and 1000. The tabs identify key strategies for adding and subtracting two- and three-digit numbers, as well as strategies students will learn in fourth grade for multiplying and dividing multi-digit numbers, and links to documents that fully describe and illustrate these strategies.
Addition Strategies Based on Place Value and Properties of Operation
Fluency is grounded in understanding. Developing an understanding of two-digit and three-digit addition begins with physical models and progresses to connecting physical and visual models to numeric representations. The learning targets for 3.NBT.2 identify the following tools, models, and strategies that students should use to build fluency with addition:
Represent addition using base ten models and and number lines
Add using partial sums (decomposing one or both addends)
Adjust numbers to add more efficiently (pictured)
For full descriptions and illustrations of these strategies, download the file linked below:
Subtraction Strategies Based on Place Value and Properties of Operations
Fluency is grounded in understanding. Developing an understanding of two-digit and three-digit subtraction begins with physical models and progresses to connecting physical and visual models to numeric representations. The learning targets for 3.NBT.2 identify tools, models, and strategies that students should use to build fluency with subtraction:
Represent subtraction using base ten drawings and number lines
Decompose numbers to subtract by counting up or counting back (pictured)
Adjust numbers to subtract more efficiently
Count up or count back to find the difference
For full descriptions and illustrations of these strategies, download the file linked below:
Multiplication Strategies Based on Place Value and Properties of Operations
The third grade curriculum requires students to be able to fluently multiply within 100 (3.OA.7) and to multiply one-digit whole numbers by multiples of 10 through 90 (3.NBT.3). The fourth grade curriculum extends this by requiring students to multiply with larger numbers using specific tools, models, and strategies to build fluency with multiplication:
Use partial products to multiply a multi-digit factor by a one-digit factor (decomposing one or both factors).
Use partial products to multiply a two-digit factor by a two-digit factor (decomposing one or both factors).
Write an equation for multiplication situations.
For full descriptions and illustrations of the strategies for multiplying multi-digit numbers, download the file linked below:
Division Strategies Based on Place Value and Properties of Operations
The third grade curriculum requires students to be able to fluently divide within 100 (3.OA.7). The fourth grade curriculum extends this by requiring students to divide with larger numbers using specific tools, models, and strategies to build fluency with division:
Represent multi-digit division (up to four-digit dividends by one-digit divisors) with models and drawings that include remainders.
Use partial quotients to divide multi-digit dividends by one-digit divisors.
Write an equation for division situations.
For full descriptions and illustrations of the strategies for dividing multi-digit numbers, download the file linked below: