‘A powerful creative act cannot be contained by a neat spreadsheet of numbers and letters. As National Curriculum Levels disappear, I’d ask you respectfully not to replace them with another set of numbers.’ 
One of the challenges facing music teachers is how to resist the demand for hard assessment data, that is, numbers and grades poorly representing musical experience. It is soft data, not hard data that tells what is worth noting, the music itself and what can be said about it. In this way assessment in music (and the arts) is primarily concerned with ‘quality’. It has a feel to it.
Assessment is first and foremost the process of giving value to the quality of the musical work in hand.  While idoceo can capture the music itself we can usefully call upon language to complement. Here are two verbal descriptions of student’s work.
Steve’s improvisations had a sense of phrasing… and was performing with a feel for the music.
Amy has realised a sense of fantasy through her thoughtful and sensitive melody writing and inventive use of sound effects.
‘a sense of phrasing, a feel for the music, a sense of fantasy, sensitive melody writing, inventive use of sound effects.’
It is language that qualifies rather than measures. This seems to be the kind of thing that Elliot Eisner  is thinking about when he proposes that assessment in the arts should focus on three things:
• Technical quality
• An inventive use of an idea or process
• Expressive power or aesthetic quality
With these priorities we start to imagine more subtle success criteria and quite different from those assessment criteria that are little more than task criteria. Task criteria can easily be reduced to a climbing ladder exercise where quality is eclipsed and where more is better than less.
It would be reasonable to suggest that students expect their work to have ‘expressive power’, that they have been ‘inventive’ and that in their work is ‘technical quality’.
The challenge will now be to discover the source of ‘powerful creative acts’.
 Perhaps the question is: when are numbers and grades valuable? Public examinations make use of these as a summative declaration of a standard reached.
The Assessment for Learning fad may have been a distraction from valuing what is here now.
 See Eisner, E. (2002) ‘The Arts and the Creative Mind.’ London: Yale University Press.