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.
Explain 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.
Arkansas Academic Standards:
2.NBT.B.7
Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and the relationship between addition and subtraction; relate the strategy to a written expression or equation
Arizona Academic Standards:
2.NBT.B.7
Demonstrate understanding of addition and subtraction within 1000, connecting objects or drawings to strategies based on place value (including multiples of 10), properties of operations, and/or the relationship between addition and subtraction. Relate the strategy to a written form. See Table 1.
Common Core State Standards:
Math.2.NBT.7 or 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.
North Carolina - Standard Course of Study:
2.NBT.7
Add and subtract, within 1,000, relating the strategy to a written method, using:
Concrete models or drawings
Strategies based on place value
Properties of operations
Relationship between addition and subtraction
New York State Next Generation Learning Standards:
2.NBT.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 representation. Notes: Students should be taught to use concrete models and drawings; as well as strategies based on place value, properties of operations, and the relationship between addition and subtraction. When solving any problem, students can choose to use a concrete model or a drawing. Their strategy must be based on place value, properties of operations, and/or the relationship between addition and subtraction. A written representation is any way of showing a strategy using words, pictures, or numbers.
Understand that in adding or subtracting up to 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
Tennessee Academic Standards:
2.NBT.B.7
Add and subtract within 1000 using concrete models, drawings, strategies based on place value, properties of operations, and/or the relationship between addition and subtraction to explain the reasoning used.
Pennsylvania Core Standards:
CC.2.1.2.B.3
Use place-value understanding and properties of operations to add and subtract within 1000.
2nd Grade Math - Add Within 1000 Lesson
The sum of numbers with more than one digit can be found by adding each column from right to left, starting with the ones place.
Example:
Step 1: Write the second number under the first number so that the ones, tens, and hundreds places are lined up.
Step 2: Add the ones column (3 + 4 = 7). Write the 7 in the ones place of the sum.
Step 3: Add the tens column (5 + 7 = 12). 12 has two digits, but both digits will not fit in the tens place. So, write the 2 in the tens place of the sum, and carry the 1 to the hundreds column. This is called regrouping.
Step 4: Add the hundreds column (1 + 2 + 1 = 4). Write the 4 in the hundreds place of the sum.