Computer shortages and faulty equipment are largely to blame for weak standards in ICT in almost half of the Welsh secondaries inspected by Estyn last year.
The subject becomes compulsory in Wales for all post-14 pupils from September 2008, as part of a review of the national curriculum. And more than pound;70 million has been injected into ICT by the Assembly government since 1998 - including the provision of whiteboards for all primary and secondary schools.
However, in primary schools, pupils' ICT skills are not as well developed as their abilities in numeracy, reading, writing, listening and speaking.
In secondaries, the number of pupils taking the full GCSE exam dropped significantly last year, though there was a big rise in take-up of the short course GCSE.
And although the number of secondaries where pupils have good skills has increased a lot, in nearly half of those inspected in 2004-5 they remain weak.
"This is often because there are not enough computers, or because ICT equipment does not work properly," says chief inspector Susan Lewis, in her annual report for 2004-5.
Brian Rowlands, secretary of the Association of School and College Leaders Cymru, said funding for ICT was a postcode lottery, and that Wales was lagging behind England.
"In some LEAs, nothing is included in the local funding formula for ICT.
Many schools are struggling to provide basic equipment let alone keep up to date with necessary upgrades. Where investment in ICT has been made it is usually at the cost of another important budget," he said.
"An average-sized comprehensive school needs something like pound;100,000 annually to invest in ICT leasing. This has to come out of savings made elsewhere.
"Broadband was installed through Assembly government funding, but no funding was provided for the running costs - another example of pump-priming without sustainability."
But the Assembly claims raising ICT standards in Wales is not simply a question of how many computers are available in schools. A spokesperson said the numbers of pupils to computers has improved from 18:1 to 8:1 in primary and from 11:1 to 5.5:1 in secondary over the past five years.
And a working group has been set up to investigate how Welsh schools - particularly in small and rural areas - can make more effective use of ICT.
Work is also going on in Scotland, Northern Ireland and England to develop an ICT self-assessment framework.
Initiatives already in place in Wales include the broadband lifelong learning network which has been rolled out to 98 per cent of schools, while all secondaries and most primaries have broadband. In England, 99 per cent of secondaries and 81 per cent of primaries have high-speed internet connections. Westminster has set aside pound;144m in 2005-6 to fund broadband connections.
Ofsted says more than half of England's secondaries are now well-equipped for ICT, with problems remaining in only one in 10 schools. Pupil achievement is also good in more than half of secondaries, and unsatisfactory in one in seven.
ACCAC, the qualifications, curriculum and assessment authority for Wales, says schools will be expected to enter all pupils "who would benefit" for ICT exams from 2008, whether GCSEs, entry level or key skills tests.