Common Core State Standards
CCSS.Math.Content.3.OA Operations and Algebraic Thinking
CCSS.Math.Content.3.OA.D Solve problems involving the four operations, and identify and explain patterns in arithmetic.
CCSS.Math.Content.3.OA.D.8 Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.
CCSS.Math.Content.3.NBT Number and Operations in Base Ten
CCSS.Math.Content.3.NBT.A Use place value understanding and properties of operations to perform multi-digit arithmetic.
CCSS.Math.Content.3.NBT.A.2 Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.