MaryKatherine:
I've kind of found with all standardised testing, that in general it is far better to have gradually accrued the full spectrum on knowledge than cram at the last minute.
Look, it sounds like he's doing a lot at school and the school clearly are pretty wound up about getting some to that prized Level 6 (most likely because it reflects well on their performance figures) - but do absorb that come senior school - yes of course they'll take into account his KS2 SATs results and that will be the indicator from which his performance will be measured throughout secondary - but they'll also test him all over again themselves and repeatedly.
This kind of constant practice papers thing was definitely what DD1 went through and it is a hard slog. Worse yet post SATs in Y6 it was just party time/ marking time - with nothing serious happening - just lots of field trips, class play, leaving party, 'business project', photography project etc...
I get that many parents want their children to do well on the test - especially in areas where they set based on KS2/ internal school (?CAT) testing (often done during the 'moving up' day/ first weeks of Y7 in a very relaxed way) - but in general it should be review just now.
So if you don't want to follow ChristinaRosetti's advice (give him a break, after all the test is next week anyway) - then my advice would be to encourage him to play maths video games on-line - to practice skills in a less obviously I'm doing problems for SATs way.
BBC bitesize KS2: www.bbc.co.uk/bitesize/ks2/maths/ is a great place to start. It will help him review the full range of curriculum he needs to have mastered without necessarily feeling much like work. Just encourage him to play something different from the last time and he'll work his way through.
HTH
Just as an aside if anyone from OFSTED is out there - I think you really do need to start monitoring what is going on in Y6. I tried to raise this with Nicky Morgan here on MN at some point because DD1 spent most of Jan - May Y6 with curriculum reduced to just English/ Maths - largely practice SATs papers and only PE or school assemblies as a break a few times a week. It just strikes me that too many schools are not adequately pacing work in YK - Y5 - so Y6 becomes this mad dash to get pupils to NC L4+ - and in this area at least get as many to L5 as possible. It makes it a very odd year for the children - and really turns them off school. It's not necessary if a school is doing their job by their pupils and, from my perspective, rather smacks of poor preparation/ planning of curriculum content/ pace of work on the part of the school.