Hi Schmee:
This may help: www.gov.uk/government/uploads/system/uploads/attachment_data/file/239129/PRIMARY_national_curriculum_-_Mathematics.pdf
this is the new national curriculum for maths (published Sept 2013) and will be in place from September 2014.
You can see right from Y1 they are introducing concepts of division - but in stages (so maybe halving is understood or sharing out/ then possible using multplication fact knowledge to cope with simple problems - so 300 divided by 3 = 100 is relatively easy because you know 3 divided by 3 is 1. I suspect from this point (Y2/ Y3) it gets more complicated and depends on how enamored of chunking a school is or is not.
Y3 new curriculum for division:
Pupils develop efficient mental methods, for example, using commutativity and associativity (for example, 4 × 12 × 5 = 4 × 5 × 12 = 20 × 12 = 240) and multiplication and division facts (for example, using 3 × 2 = 6, 6 ÷ 3 = 2 and 2 = 6 ÷ 3) to derive related
facts (for example, 30 × 2 = 60, 60 ÷ 3 = 20 and 20 = 60 ÷ 3).
Pupils develop reliable written methods for multiplication and division, starting with calculations of two-digit numbers by one-digit numbers and progressing to the formal written methods of short multiplication and division.
Y4 new curriculum for division:
Pupils practise to become fluent in the formal written method of short multiplication and short division with exact answers (see Mathematics Appendix 1 - last two pages of document I attached).
Y5 new curriculum for division:
divide numbers up to 4 digits by a one-digit number using the formal written method of short division and interpret remainders appropriately for the context
multiply and divide whole numbers and those involving decimals by 10, 100 and 1000
and Y6 new curriculum for division:
divide numbers up to 4 digits by a two-digit whole number using the formal written method of long division, and interpret remainders as whole number remainders, fractions, or by rounding, as appropriate for the context
divide numbers up to 4 digits by a two-digit number using the formal written method of short division where appropriate, interpreting remainders according to the context
see Appendix 1 (pp 46-47) for calculation methods - at end of document.
HTH