The working at, below or on target is open to abuse imo. The interpretation of the national curriculum targets by both primary schools my children went to were:-
only the bottom 20% work below the "expected" level"
and theoretically, only the top 20% were above the expected level. Leaving 60% working "at" - but I think there is a big difference between at no. 21 and being at no. 79....
However, then the school would take it further. You had to be below the minimum level to be working below - so still the bottom 20%, but now anything even slightly above the minimum cut-off was called "working above expectations".
So, in the end it was:-
lowest 20% were "below expectations"
Next 20% (say) were "working at expected levels"
and 60% was "above expectations"
So, you have a genuinely clever child, and you want the teacher to teach him /her throwing in the odd day when the work offers some challenge, but all you got was "they are working above expectations" and you knew that only meant they were being set more challenging work than the bottom tow tables. However, at least you could argue in terms of sublevels progress, but now you can't because the new system can cover everything up.
(I realise I've not explained this very well- hope you get my meaning anyway!)