Addition with regrouping and carrying over is not easy to remember for the child.
My way of teaching my daughter was to teach her about two different houses - tens and ones.
Ones cannot have more than one digit at any point of time. So when two numbers in the ones place add to more than 9, there is an extra number. Since ones cannot have more than one digit, this other number has to be given a new house. This digit is added to the tens house because tens house can still take in more numbers. And then you add the numbers in the numbers place. This story combined with carry over table and column, helps the child remember.