Failure rate of FE college students disappoints experts, Karen Thornton and Nicola Porter report.
College students taking the Welsh baccalaureate are twice as likely to fail the new qualification as school sixth-formers.
Only 15 per cent of the 159 school pupils who completed the advanced diploma programme failed to gain the award, compared to 32 per cent of the 145 completers studying in further education colleges.
The figures - released last week with the A-level results - were overshadowed by others recording the high drop-out rate from the baccalaureate. Just over a third of the 670 pupils expected to take part in the two-year pilot gained the advanced diploma.
Other figures show more than twice as many girls as boys completed their studies and collected a baccalaureate. But the pass rate was higher for boys than girls (79 per cent versus 76 per cent).
Experts say they would expect results to be lower in colleges than schools - but not for the failure rate to be twice as high. Professor David Reynolds, of Exeter university, said: "My impression is there was also huge variability between individual schools and colleges. It's worked in some places, and we've got to find out why, and benchmark against them."
Heledd Hayes, education secretary of the National Union of Teachers Cymru, suggested schools had better pastoral support. She said: "In the colleges, you are expected to be an adult and it's up to you to sort your work out.
Schools traditionally look out for pupils and offer help."
John Graystone, chief executive of fforwm, which represents most of Wales's FE colleges, felt colleges had probably done better in equipping young people with the key skills required by the bac. But there may not have been enough awareness early on of the need to complete all its requirements - including key skills, an individual assignment, work experience, study of Wales, Europe and the world - to attain the full award.
"We have to learn lessons. It is a pilot and we are confident we will see a vast improvement next year," he said.
Others point to differing approaches, with colleges offering the course to volunteers while many schools expected a whole year group to study the bac.
Shirley Minton, Welsh bac co-ordinator at Deeside college, Flintshire, said it had only five students take the bac, on a voluntary basis: "Schools have embraced it hard-core, while colleges are offering it on a voluntary basis." But she said it was too soon to criticise the bac, which she described as an "innovative and exciting" change from traditional A-levels.
The baccalaureate pilot was launched two years ago in 16 schools and colleges.
The WJEC, the Wales exam board, is evaluating this summer's results.