One of the main aims of the national curriculum is that everyone should be able to use Standard English when writing. The grammar work found on the site is aimed at this but we have also just published four sets of worksheets concentrating on the difference between Standard English and non-Standard English. Each concentrates on a different aspect:
1. subject-verb agreement
2. irregular verb forms
3. correct use of apostrophes
4. double negatives
These are all written for older primary school children and are well worth a look, together with all our other detailed grammar pages.