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 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.

  Addition   

• Add two three-digit numbers
• Addition input/output tables - up to three digits    
• Complete the addition sentence - up to three digits 
• Balance addition equations - up to three digits

Subtraction

• Subtract three-digit numbers
• Subtraction input/output tables - up to three digits
• Subtraction word problems - up to three digits
• Complete the subtraction sentence - up to three digits
• Write the subtraction sentence - up to three digits
• Balance subtraction equations - up to three digits