Headships and management in two neighbouring colleges is poor, inspectors say in scathing reports published last week.
They graded management at Southgate and Enfield colleges in north London unsatisfactory and ordered them to improve.
At Southgate college, eight of the 12 curriculum areas examined by inspectors from the Office for Standards in Education received an "unsatisfactory" grade 4.
At Enfield college, three of the 11 areas inspected were considered "unsatisfactory", but inspectors said that represented a third of the college's courses.
Funding chiefs announced this week that they are "disturbed" by the inspectors' findings and said they will be working closely with both colleges to "ensure that they address the weaknesses identified in these reports as rapidly as possible".
The Learning and Skills Council said in a statement: "The Ofsted recommendations indicate that the colleges need to take some significant management decisions to ensure that students have satisfactory provision.
"The LSC is obviously very concerned about the amount of inadequate provision and the leadership and management issues identified in the inspection, but will be working with the college to improve what is not working well."
At Southgate college, where the principal, Michael Blagden, earns more than pound;105,000 a year in salary and emoluments, steps have already been taken to strengthen the management.
Last Friday, the same day the inspection report was published, a director of quality was appointed "to ensure the consistent application of quality across the college".
Mr Blagden told The TES: "We are shocked at the outcome of this inspection as we have passed previous inspections with flying colours. Clearly the college is hurting from these latest findings.
"The governors are determined to work with the management to drive through the improvements that are being required. Ofsted has identified a number of areas where we must improve and we are determined to respond positively and to rise to the challenge. "We are already tackling those issues with gusto and with the aim of ensuring that Southgate college will provide the levels of excellence for our students, for which we have long had a proud reputation."
He said a major reason for the college's poor report was that the inspection was carried out last October, just one month after a tougher inspection regime came into force.
He added: "In the previous inspection, management was awarded a grade 2 and 60 per cent of our curriculum areas were graded as good.
"It is not so much that the staff has changed, but the criteria by which we were inspected."
Ofsted said of Southgate college: "Leadership and management are unsatisfactory. Several issues identified in the last inspection have not been addressed with sufficient determination to bring about rapid improvements in students' experience.
"There has been little improvement in the quality of provision over the past four years and some aspects of provision have deteriorated. The quality of students' experience in some subjects is unacceptable."
Of Enfield college, Ofsted said: "The quality of teaching and learning has deteriorated since the last inspection and the proportion of unsatisfactory teaching is above the national average.
There are significant weaknesses in the leadership and management of some of the curriculum areas."
Both colleges now have two months to prepare action plans to show how they will address the issues highlighted, which need to be approved by the LSC and Ofsted.
In a third Ofsted report published last week, one college received glowing praise. The Isle of Wight college was graded "outstanding" in one curriculum area, "good" in five, and "satisfactory" in three.
Teaching was classified as "good" or "better" in 69 per cent of sessions observed. Leadership and management were described as "good" and the leadership provided by the principal was said to be "exemplary".