Do pupils behave differently towards male and female teachers?
On the face of it, a recent NUT survey seems to suggest that men have a tougher time from pupils.
The union asked 1,500 members what sort of poor behaviour they tackled each week. It found that 80 per cent of male staff said they were on the receiving end of backchat from pupils, but only 70 per cent of female teachers reported the same - a comparison that prompted many newspaper headlines last week.
Just over half of male teachers said they had to cope with defiance from pupils, compared with about 40 per cent of females.
Three-quarters of male teachers faced disruption of their lessons - higher than in a similar survey of 2001 - whereas around two-thirds of women reported the same problem, less than in 2001.
And 68.9 per cent of men were sworn at, compared with 56.6 per cent of women.
But the difference may not be because of gender.
There are more than three times as many men teaching in secondaries than in primaries, according to government figures.
Dr Sean Neill, of Warwick University's Institute of Education, who carried out the survey, said that once the educational phase - primary or secondary - was allowed for, the gender effect did wash out.
This finding tallies with previous research, which gives some idea not of the comparison between the gender of teachers, but of the scale of the difference in behaviour between primary and secondary.
For example, in June 2008 the National Foundation for Educational Research questioned a representative sample of 1,400 teachers for the Department for Children, Schools and Families.
Only 19 per cent of secondary teachers questioned said pupil behaviour was "very good", compared with 31 per cent of primary teachers. At the other end of the scale, 9 per cent of secondary teachers said pupil behaviour was "poor", compared with just 4 per cent of primary teachers.
Kenny Frederick, head of George Green's School in east London, said: "I can't say I've noticed pupils' behaviour is worse with men. If you are talking about aggressive boys, it may be they won't have confrontations with women in the same way as they would with a man, but I think it's more to do with individual teachers.
"Certainly children do adapt their behaviour to different teachers; they know exactly what buttons to press. But that happens whether the teacher is male or female."
The NUT survey gives some idea of the scale of disruptive behaviour - most teachers have lessons disrupted weekly. It also gives an indication of how things have changed since 2001.
"What we get with a lot of behaviour is that it has become polarised," said Dr Neill. "There are relatively more people who never or very rarely experience a certain behaviour, but also relatively more who experience it frequently.
"Refusal to work, for example, had slightly more teachers who experienced that every week, and slightly more who never experienced it, with a lower proportion experiencing it on a monthly or termly basis."
Recent research that tried to measure behaviour objectively by observing pupils in 141 primary classrooms found that pupils concentrated on work for 85 per cent of the time: the highest rate in the past 20 years.
Dave Fann, head of Sherwood Primary in Preston, agreed that this was the trend: "I think behaviour is better in 2008 than I remember it being in 1988. In my experience, children in primary schools are generally better behaved.
"I think that comes from teachers talking about pedagogy - what makes a good lesson - and being more open about what goes on in the classroom."
Looking at the longer term, the union's survey gives an indication of what can prevent poor behaviour in the first place. Dr Neill found the support teachers get could be an important factor. "Better support for teachers meant less disruption, but better support for pupils didn't seem to have the same outcome," he said.
But teachers had to feel they could ask for support. One young man teaching in a secondary school wrote on the survey form: "It can often feel like an admission of failure to ask for help."
The union found 60 per cent of the members surveyed said they had not received any behaviour training. Only 15 per cent of male and 18 per cent of female teachers said support with difficult pupils was excellent.
The National Foundation for Educational Research report made a similar finding. While 83 per cent of respondents felt they could manage pupil behaviour, only 35 per cent felt there was appropriate training available for struggling teachers.
Christine Blower, acting general secretary of the NUT, summed up the problems faced by teachers dealing with poor behaviour in the following way: "We can't afford to neglect teachers who daily make a positive difference to the lives of young people from the toughest backgrounds. Neither can extra support for these teachers be subject to preconceived notions about whether male or female teachers are better at tackling unacceptable behaviour."