My son got a 2A in maths, he was born on 29th August so very young in the year. He's done well this year and his teacher is good but it's interesting to talk to those that know him in the school & his main class teacher and they say, 'gosh maths is a struggle isn't it' 'not his strongest point' 'a weaker area' 'So tricky for him but he's plodded on and done well through hard work'. They are not being negative but it's as if the decision has been made that come next year this will indeed be his weak area. His genes have clearly made him less strong in this area according to them. He's not got the natural ability that's so highly regarded in their opinion so will only get there through a steady plod, if he gets there at all.
I don't see why come next year he might excel? I fear it's not likely to happen because those around him subconsciously (at best) believe otherwise. He'll be working with other 'strugglers' etc. I'd still think he could excel in time if he'd got a 2B or less and actually that would be a respectable level.
This is why SATS worry me, IMO they barcode children young. I've been reading about those 'low ability' children that go on to do unexpectedly well in SAT tests and it's not thought possible. I know that continuous assessment helps to make things fair but even so parents and teachers seem to accept very early on that their child is quick or slow, bright or dim and so the die is cast.