4. 2 Digit + 2 Digit with Regrouping
Add a 2 digit number with another 2 digit number, which requires regrouping ones to make tens (or carry at ones). Understanding of regrouping ones and tens is an important step before moving on to addition using the standard algorithm, which follows in higher grades.
Common Core Alignment
2.NBT.5Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.