Removing young people from school due to bad behaviour is a waste of money, a leading children's charity has claimed.
While the number of pupils being expelled has fallen, Barnardo's said fixed-term exclusions from schools are expensive, ineffective and "over-used".
Instead, the charity suggested that focusing on the causes of the bad behaviour and working with pupils' families was a better solution.
Martin Narey, Barnardo's chief executive, said: "Barnardo's acknowledges that when behaviour is dangerous, removal from school may be the only option. But disruptive behaviour is frequently a sign of problems outside school and those young people most at risk of exclusion need more adult supervision and support, not less.
"It is madness for us to take poorly-behaved, often troubled children and remove them from the one arena in which they are required to behave reasonably.
"Ejecting them from school and leaving them to their own devices in chaotic homes and risky neighbourhoods is not going to improve anything, it's just a costly and ineffective dead-end."
The charity said that secondary schools in England issued 307,840 fixed-term exclusions from 2008 to 2009, which is more than 800,000 days of missed education. Two-thirds of such exclusions were given to pupils who had already received one earlier the same year.
Barnardo's report - Not present and not correct: Understanding and preventing school exclusions - recommended early intervention and called for a clampdown on unofficial exclusions.
It said permanently excluding a pupil can cost up to three times as much as investing in counselling or family support.