The TES has obtained a leaked report on the BBC Jam website, which is due to go online next Friday and cover half the curriculum by 2008.
The report was produced by the Content Advisory Board, a panel set up in 2003 by Charles Clarke, then education secretary, to ensure that the BBC did not take business away from private competitors.
The Department for Culture, Media and Sport agreed to let the BBC set up the free website only if it complemented services from commercial companies.
But the board expressed concern about the digital curriculum service, which "does not presently appear to complement the services provided by the commercial sector", and by a "degree of disappointment with the extent to which the prototypes demonstrated genuine technological or pedagogical experimentation".
The board is not wholly critical and recognises the difficulties the BBC had in meeting its remit. But it says the broadcaster will face further criticism from the industry and the European Commission, which has already raised concerns with the Department for Education and Skills.
"We therefore consider it essential that the issues surrounding the BBC digital curriculum service be resolved as a matter of urgency," it stated.
The board includes key figures from government departments, schools and local authorities, and is chaired by Owen Lynch, the soon-to-retire chief executive of the schools technology agency Becta, which oversees the board.
The report also points out that substantial amounts of the pound;100m per year which schools have been given in electronic learning credits (ELCs) were not used for their purpose, which was to buy educational software.
It said that the credits had benefited software houses but had not brought the hoped-for "step change" in teaching.
A BBC spokeswoman said the broadcaster found the board's report puzzling because it seemed to be based on glimpses of the website six months ago.
"The service going live next week is very different, and we urge people to go online and form their own views," she said.