Schools should not “over discipline” persistently unruly pupils for fear of alienating them and should instead hand out praise five times more often than punishments, the Government has said.

New guidance on school discipline published yesterday cautions teachers against repeatedly praising only “the same good pupils”, suggesting that rewards also be given to persistent miscreants who show an improvement in behaviour, however small. It cites research recommending a “rewards/sanctions ratio of at least 5:1”. Rewards might include “good news” postcards sent home, “special privileges” or “prizes”.

“Striking the right balance between rewarding pupils with consistently good behaviour and those achieving substantial improvement in their behaviour is important. This can help improve relations with parents who have become tired of receiving letters and phone calls when things go wrong,” the guidance states.

It also advises teachers to take account of pupils’ race and culture when telling them off, suggesting that they go easy on those insubordinate youngsters for whom being “loud” or “overfamiliar” may be a cultural norm or “social style”.

Teachers should understand the importance of showing respect to children from racial or religious backgrounds for whom public humiliation is seen as particularly shameful. In these cases, staff should not use language that might humiliate youngsters in front of their friends.

In other areas the guidance advocates a tougher approach, encouraging teachers to give Saturday and after-school detention and to punish pupils who make false allegations against teachers.

It has been published to accompany new legal powers enabling teachers to use “reasonable force” to restrain violent children, confiscate mobile phones and punish pupils for poor behaviour on their way to and from school.

But critics described the guidance as “soft”, stating that most teachers already knew how to use positive reinforcement techniques.

The document coincided yesterday with a threat of strikes by the National Union of Teachers unless schools speed up the process for expelling violent or abusive pupils.

David Willetts, the Shadow Education Secretary, said that the new guidance could be resented by pupils if it implied that bad behaviour brought rewards. He said that if school children could see badly behaved pupils being praised “then the school’s policy would lose all credibility”.

Alan Smithers, Professor of Education at the University of Buckingham, said the move could encourage perverse behaviour. “Children and parents will be quick to pick up on false praise. That simply devalues the use of encouraging words. The key thing is that it has to be honest feedback. As a soft approach it won’t work because children and their parents will soon pick up that it’s false.

“If you reward the children who have been poorly behaved for behaving well you might actually be getting children who have been perfectly happy behaving well to behave badly in order to pick up the rewards.”

Robert Whelan, deputy director of the thinktank Civitas, said: “The idea that teachers have to take account of a child’s ethnicity when disciplining them is racist. It’s telling teachers they have to treat children differently according to their skin colour.”

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