The results of last year's tests show rural schools achieving the best averages, with areas of high unemployment among the worst.
Unlike in England, where school-by-school results are due to be published on March 11, individual Welsh schools will not be included in league tables.
Instead, tables published by the Welsh Secretary William Hague compare each of the 22 new unitary authorities set up last year.
The tables give LEA averages for key stage 2 tests, together with scores based on teachers' own assessments in English, maths, science and Welsh (see right).
Average test scores for Wales are higher than those for England, with 60 per cent of 11 year-olds achieving level 4 in English, compared with 58 per cent in England. Figures for maths are Wales (62), England (54). Figures for science are Wales (68), England (62).
Monmouthshire, the Vale of Glamorgan, and Powys are among the top-performing LEAs, while the former mining communities of Merthyr Tydfil, Caerphilly and Blaenau Gwent are among the worst. Also near the foot of the table is the capital, Cardiff.
Brian Mawby, director of education for Blaenau Gwent, an authority which includes former mining towns such as Tredegar and Ebbw Vale, said: "The results are not unexpected. There is a need to adjust education funding to take care of problems in areas like the old South Wales coalfield. If there was a league table of the take-up of free school meals, authorities in such areas would come top, with the more affluent areas at the bottom."
David Winfield, secretary of the National Association of Headteachers in Wales, agreed. He said: "The results can be directly related to the financial state and social fabric of the different areas." Cuts in school budgets were prompting an exodus of teachers at a time when target setting was on the increase, he claimed.
One surprise is the comparatively poor results in Welsh in areas where the language is strongest. Teacher assessments put the percentage of 11-year-olds in the Isle of Anglesey at 42.5 per cent, compared with 51.3 per cent in Pembrokeshire, a county known as "Little England Beyond Wales". For Gwynedd, where more than 70 per cent of the population speak the language, the score was 57.7 per cent. The authority is the only one controlled by Plaid Cymru.
The figures also show that Welsh girls outperform boys at 11. While 49 per cent of girls reached level 4 in all four subjects, only 42 per cent of boys did so. The gap widens further as pupils progress. In 1996 47 per cent of 16 year old girls achieved 5 or more GCSEs at grades A to C, with boys rating only 37 per cent.
The Welsh Secondary Schools Association is to organise a course for teachers aimed at tackling boys' under-performance. Lyn Clement, its general secretary, said: "Boys tend to be more speculative, more interested in dealing with ideas, while girls tend to be more thorough in their approach to analysing direct experiences."
The Welsh Office junior minister in charge of education, Jonathan Evans, urged LEAs and schools to use the data as a basis for improving achievement. He said: "For 11-year-olds we would expect as a minimum that 60 to 70 per cent should achieve level 4 or better by the year 2000."