Now your child has practiced addition in columns without carrying, they are ready to understand why the ten needs to be carried across to the tens column.
Explain that any number greater than 9 can not be written in the units column. They will need to partition the number into tens and units and write the additional ten below the tens column ready to be added. Again reinforce that we always begin with the units column.
If they cross out the additional ten when adding, it will encourage fewer mistakes when adding mentally.
Watch the clip below to practice with your child.