A multi-billion pound adult literacy and numeracy strategy has done little to improve standards, a report says.
The Skills For Life programme has been running since 2001
The Department for Education and Skills (DfES) looks likely to spend nearly £6bn on the Skills For Life programme.
But the House of Commons public accounts committee says the first few years of the scheme have provided "little evidence of improvements".
The government says that, because the programme started from such a low base, it is too soon to see progress.
The DfES's strategy for the UK - which has low levels of adult literacy and numeracy compared with its international competitors - aims to improve the skills of 2.25 million adults by 2010.
Although the department is on course for that, the report, published on Tuesday, calls into question the quality of teaching and the scheme's cost.
"The quality of provision for adults with literacy and numeracy needs is still too low," the report said.
It cites the "widespread weaknesses" found in an extensive quality review by Ofsted and the Adult Learning Inspectorate.
And it goes on to say that people in the greatest need are receiving the worst provision.
In colleges, literacy, language and numeracy provision was poorer than for other areas of learning, the report said.
"In the first three years of the strategy, inspections have shown little evidence of improvements," the report said.
"A further evaluation of the quality of provision by Ofsted and the Adult Learning Inspectorate one year on from their first review found no such evidence either," it added.
The government has spent £3.7bn on the scheme since its introduction in 2001.
The report said it was not known how much more money would be needed over the lifetime of the programme, but it is said it could be more than £2bn on current spending levels.