A fifth of 61 behaviour support plans surveyed by education and training charity Rathbone CI did not mention looked-after children or set targets for them.
Ministers want 50 per cent of looked-after children to achieve a qualification - at least one graded GCSE - by 2001, and 75 per cent by 2003. Last year, 93.4 per cent of all England's 16-year-olds achieved this standard.
A TES survey earlier this year found at least 47 councils had set targets for improving looked-after children's performance without knowing how well they currently do.
The Government has also called on education authorities to reduce exclusions among looked-after children - up to 80 times more likely to be expelled from school than classmates who live at home. However, no specific exclusion targets have been set.
Carol Toms, Rathbone CI's policy officer, said: "The targets the Government has set are very minimal, and local authorities are copying what it says.
"We think behaviour support plans should state the numbers of looked-after children, their exclusion rate, and the number with statements of special educational need.
"All schools should have a link teacher, and a tutor should be available to support children in residential care who are without a school place, for whatever reason."
Authorities praised by the Manchester-based charity include Derby, which states that all its schools have a teacher responsible for looked-after children, and Redcar and Cleveland, which has an education link person in each children's home.
Rathbone CI has a free helpline for advice and information on exclusions and behaviour issues, telephone 0800 9176790.
8 News TESJmay 28 1999 barry greenwood On-side: Manchester City captain Andy Morrison, who has had discipline problems on and off the field, with pupil Johnny Ramsden, 11