Most primary schools are already giving pupils foreign language lessons during class time, but the vast majority do not assess how the children are doing.
An unpublished report into the state of language teaching in primaries last year highlights the rapid progress schools have made in introducing lessons in the subject, which is not due to be compulsory until 2011.
But the findings also show that most primaries do not assess pupils' language skills, and that many are concerned that their work is wasted when children go on to secondary schools.
The full report was not due to be published until 2009, but was obtained by The TES through a Freedom of Information Act request.
It is the second in a series of three reports on primary language teaching commissioned by the Government from the National Foundation for Educational Research (NFER).
Researchers surveyed around 2,800 schools and are keeping track of a further 500, which have been selected to ensure a representative sample.
A summary of the report, published in June, revealed that the proportion of primary schools offering modern languages had risen from 70 per cent in 2006 to 84 per cent a year later. It noted that schools "in more difficult circumstances" were less likely to teach languages.
The full report shows that 63 per cent were not able to provide details of any monitoring or assessment programme to track their pupils' progress. Those that did were most likely to use their own assessment materials. Many were concerned about the transition to secondaries, when work their pupils had done on languages could be ignored and wasted.
One school told the researchers: "This is a great concern. We've made secondary schools aware, but parents of children who have transferred to secondary school have informed me that their children are being placed in classes with beginners as the secondary schools are not equipped to deal with children coming in with significantly high levels of language skills."
The report said the responses concerning transition to secondary schools were not encouraging. "Twenty per cent did not respond to the question on transition and 40 per cent of the responses were negative," it said.
The problems with transition have also been noted in a separate report by Cambridge University, which focused on language teaching at secondary level. It found that key stage 3 teachers took little account of pupils' work in primary schools.
Only 6 per cent of secondary departments said they used prior language learning to inform grouping at Year 7, while a quarter stated that they grouped Year 7 classes irrespective of pupils' primary experience.
The failure of secondaries to build on primary language learning is particularly significant as this was one of the reasons for the collapse of a pilot scheme to introduce French teaching into primary schools during the 1970s.
The NFER report also revealed that 11 per cent of schools in the richest areas did not offer languages, compared with 24 per cent of those in the poorest areas.
The North East is still the area with the best provision - 91 per cent of schools offer languages in class time, compared with 79 per cent in 2006.
Only two regions - the West Midlands and London - remain where more than one in five schools is failing to offer languages in class time, compared with all nine regions in 2006.
Rekha Bhakoo, head of Newton Farm First and Middle School in Middlesex, said she was planning to arrange training for her teachers in French teaching so that more of them could provide lessons.
"We have taught French from Year 1 upwards for the past two or three years, and I think it is wonderful," she said.
"We have a French specialist, who comes in on a part-time basis and we have two teachers who are fluent French speakers already. But there isn't anything for the other class teachers - that's where we're struggling."
2002: overnment says all key stage 2 pupils will have the chance to study a modern foreign language by 2010
2003: National primary strategy created to bring together literacy and numeracy. First strategy document, "Excellence and Enjoyment", encourages primaries to be more creative with the curriculum
2006: New frameworks introduced for the literacy and numeracy strategies, which include more guidance on speaking and listening
2007: Phonics teaching becomes compulsory
2008: Interim report from Sir Jim Rose's primary curriculum review due in the autumn term
2009: Final report from Sir Jim Rose's primary curriculum review and Professor Robin Alexander's primary review due in the spring term
2010: Every KS2 pupil to have the opportunity to learn a foreign primary review due in the spring term
2011: All primaries legally required to teach a foreign language. New curriculum due to be introduced.