Dyscalculia: News from the web:
What pupils who makes errors due to limited understanding of place value is definitely DO NOT is need more practice of column addition and subtraction. In most cases pupils need to secure their understanding of what happens to tens and ones when counting up and down – regrouping ten ones for a ten when counting up and regrouping ten ones for ten when counting down. Once secure with this they need to be able to regroup numbers into hundreds, tens, ones in a number of ways.
Read all about it: HERE