In some cases, results have yet to hit targets expected by 2002. But standards of teaching and learning in Welsh schools have improved over the past five years, and test results have risen in key stage 2 and KS3, according to inspection agency Estyn's annual report, published this week.
An Assembly government spokesperson said most of its targets were set before the Assembly was established, and were used "in the absence of other data".
Headteachers have called for policy-makers to revise their targets, saying schools could be blamed for failing to hit them despite some significant improvements in performance.
In her annual report, Susan Lewis, chief inspector of education and training in Wales, says the education sector has "much to celebrate", particularly in early-years and special-needs provision. In secondary and primary, the Assembly government's 2007 target for the percentage of classes with good and satisfactory standards (65 per cent) has already been passed.
But she warns that the GCSE pass rate for five or more A*-G grades has remained "static" at 85 per cent for the past five years, and too many pupils are leaving school with few or no passes. Results for five or more A*-C grades have risen from 49 to 51 per cent.
Last year's GCSE results fell well short of the targets set out in The Learning Country, the Assembly government's 2001 statement of its education plans.
Ministers wanted 58 per cent of pupils to achieve five or more A*-C grade passes in 2004, and 95 per cent - 10 percentage points higher than the current pass rate - to get five or more A*-G grades.
Despite significant improvements in test results for 11 and 14-year-olds, further Assembly targets have been missed for these age groups.
For example, at KS2, test results are much better than five years ago, and are now just above those of 11-year-olds in England. The percentage of those achieving level 4 in Welsh or English, and maths and science, has also increased from 63 to 72 per cent. But this remains a long way short of the Assembly government's "core subject indicator" target of 80-85 per cent by 2004-7.
Brian Lightman, of the Secondary Heads' Association Cymru, said: "Where did they get these targets from, were they based on pupils' previous attainment?
"Schools are improving a great deal and it would be unfortunate if a failure to hit these targets was seen as a failure of schools."
Jane Davidson, minister for education and lifelong learning, said: "Most of the targets were set before the Assembly came into being. We used these targets in the absence of other data and, as we develop our evidence base, we will review them accordingly. The key point is that standards of education across the board have risen."
welsh voice 22