## ◂Math Worksheets and Study Guides Second Grade. Addition Facts

### The resources above correspond to the standards listed below:

#### Colorado Academic Standards (CAS)

CO.2.1. Number Sense, Properties, and Operations
2.1.1. The whole number system describes place value relationships through 1,000 and forms the foundation for efficient algorithms. Students can:
2.1.1.b. Use place value understanding and properties of operations to add and subtract. (CCSS: 2.NBT)
2.1.1.b.i. Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction. (CCSS: 2.NBT.5)
2.1.1.b.ii. Add up to four two-digit numbers using strategies based on place value and properties of operations. (CCSS: 2.NBT.6)
2.1.1.b.iii. Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. (CCSS: 2.NBT.7)
2.1.1.b.v. Explain why addition and subtraction strategies work, using place value and the properties of operations. (CCSS: 2.NBT.9)
2.1.2. Formulate, represent, and use strategies to add and subtract within 100 with flexibility, accuracy, and efficiency. Students can:
2.1.2.b. Fluently add and subtract within 20 using mental strategies. (CCSS: 2.OA.2)
2.1.2.c. Know from memory all sums of two one-digit numbers. (CCSS: 2.OA.2)