Fiona Hyslop has insisted progress is being made on cutting class sizes
First Minister Alex Salmond has been forced to defend his education secretary, as the political row over cutting class sizes intensified.
Labour and the Conservatives branded Fiona Hyslop "hapless" and said she was "making a fool" of Mr Salmond, amid claims a key SNP pledge was ditched.
The attacks came after Ms Hyslop did not contribute to a Labour-led Holyrood debate on the issue.
But Mr Salmond said pupil achievement in Scotland was at a record high.
During heated exchanges during first minister's questions, he insisted the Scottish government was making year-on-year progress to hit education targets - something he said Labour failed to do during its time in power.
The row blew up after Ms Hyslop announced plans on Wednesday to cap class sizes in primary one at 25 pupils - while denying the plan would mean dumping a manifesto promise to reduce early primary classes sizes to 18.
She said the 25-pupil limit would provide a "backstop" for local authorities facing legal challenges.
Going on the attack, Scottish Labour leader Iain Gray claimed: "The first minister was elected on a false prospectus.
"In a tight election, he made cynical promises to children, parents, teachers and students - promises he never intended to keep.
"The education secretary is making Alex Salmond look like a fool."
Criticising the SNP's record in education, Annabel Goldie, told MSPs: "Posted missing in making any comment to this parliament about this mess is the minister, the hapless Fiona Hyslop."
She went on: "Who should the parents blame for this mess? The cocky head boy Alex Salmond or his silent and wretched prefect, Ms Hyslop."
Mr Salmond told MSPs the standard grade pass rate was 98.5% in 2009, while the pass rates for higher exams and advanced highers were 74.2% and 77.8% respectively. He added: "Each of these statistics is a new record of achievement in Scottish education."
The first minister said of Ms Hyslop: "I will put on record the approval and the endorsement I have for an education secretary who's helped, along with the pupils and teachers of Scotland, to achieve the record levels of attainment."
Earlier, Ms Hyslop was accused by the opposition of ducking out of the Labour class sizes debate in the Scottish Parliament, after which MSPs voted by 70 to 48 to condemn the SNP for failing on key education pledges.
Although the education secretaty was present in the chamber during the event, Schools Minister Keith Brown responded for the government, insisting average primary class sizes were at a record low.