Labour leader Johann Lamont said about 7,000 school-leavers without jobs had not yet found places on education or training courses and 17,000 school-leavers had disappeared from official records.
Ministers do not know what the youths “are doing”, she told First Minister’s Questions last week.
“The First Minister promised that no young person would be left behind. He cuts college funding,” Ms Lamont said.
However, Mr Salmond, the first minister, insisted there had been “substantial progress” on youth unemployment, and the total of those out of work had fallen by a third in Scotland.
“During the most difficult economic climate, we have hugely increased the number of Apprenticeships,” he said.
Earlier this month the Scottish government and Skills Development Scotland said they had met a target to create 25,000 Apprenticeships a year for the second year running.
Meanwhile, the rate of Scots in higher education (college or university) has reached a record high of 56.1 per cent, up from 55.6 per cent in 2011 and almost 10 percentage points higher than in England, where it is 46.5 per cent.
However, uptake by students from wealthier areas rose to 59.9 per cent from 59.1 per cent last year. This compares with a drop for those living in the most deprived postcodes – to 39.1 per cent from 39.7 per cent, according to a report by the Scottish Funding Council.
The proportion attending university in Scotland has reduced slightly, with the decline being made up by an increase in those studying higher education courses at college.
Angela Constance, minister for youth employment, said she was “delighted” by the record participation rates. She added: “The participation rate in Scotland is also considerably higher than in England and these record figures reinforce the Scottish government’s belief that education should be based on the ability to learn and not the ability to pay.”