Chapter 3

Upon completion of Unit 3:

• 2.NBT.A.1. Understand that the three digits of a three-digit number represent amounts of hundreds, tens, and ones; e.g., 706 equals 7 hundreds, 0 tens, and 6 ones. Understand the following as special cases:
• 2.NBT.A.1a. 100 can be thought of as a bundle of ten tens — called a “hundred.”
• 2.NBT.A.3. Read and write numbers to 1000 using base-ten numerals, number names, and expanded form.
• 2.NBT.B.5. Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.
• 2.NBT.B.6. Add up to four two-digit numbers using strategies based on place value and properties of operations.
• 2.NBT.B.7. 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. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
• 2.NBT.B.9. Explain why addition and subtraction strategies work, using place value and the properties of operations.
• MP.4. Model with mathematics.
• MP.5. Use appropriate tools strategically.