high levels of underachievement by Somali pupils have been masked by government statistics.
Only a third of Somali children in London achieved five GCSEs at grades A* to C. This is worse than all African pupils 51 per cent of them reached this level, against 59 per cent of all pupils nationally.
But Somali pupils are classed among black African groups in government measures of achievement, preventing schools from observing patterns of failure. London local authorities collated their own statistics from last year's GCSE results.
Between 95,000 and 250,000 Somalis live in Britain, concentrated in cities. Feyisa Demie, who compiled the report for Lambeth, believes many are traumatised by the civil war that forced them to leave Somalia. Others live in overcrowded accommodation, and 87 per cent of Somali pupils taking GCSEs are not fluent in English.
"Racism, poverty and some teachers' negative perceptions of Somali children's abilities are adding to their problems," he said.
"This is an issue policymakers, schools and parents must address. The underachievement, disaffection and disengagement experienced by many Somali teenagers are a real cause for concern."
The statistics show that Somali underachievement begins early: only 58 per cent of Somali children reached the expected level 4 in maths at key stage 2. The national average is 75 per cent.
But Mr Demie said many London schools were working hard to engage Somali pupils and parents, with some looking for staff and parent governors from the community.