Should schools be telling parents what they can and cannot put in a packed lunch? Whether or not they should let their children cycle to school? Which websites they should allow their children to access?
There is a fine line between giving parents advice and bossing them around. While schools have a duty to look after children in their care, they need to know when to step back - otherwise toes get trodden on.
"No parent takes kindly to being told how to bring up their child and it's unacceptable for any school to do that," says Margaret Morrissey of the campaign group Parents Outloud. "Saying what time children should go to bed, for example - that's nothing to do with schools. Each child is different, and parents know their children best."
But many heads say parents appreciate advice on bringing up their children, provided it is offered in the right spirit.
At St Michael's RC Primary in Liverpool, where parenting classes are hugely popular, head Tony Hegarty says respect is key. "I never judge parents because I don't know what their lives are like," he says. "But if we thought a pupil wasn't getting enough sleep, we'd talk to mum or dad to find out why. Parents occasionally bristle, but you have to be clear that you're not criticising them: you just want the child to do well."
Some subjects are touchier than others. With an issue like internet security, parents often lack knowledge and appreciate pointers. But sandwich fillings are another matter: a recent Ofsted report found schools which gave guidelines on packed lunches were seen as "bossy" and "interfering". More seriously, if a school has concerns about a young person's lifestyle and fears they may be taking drugs or drinking heavily, it makes sense to raise the alarm, if only because parents may be unaware.
"Schools shouldn't act on rumours," says Ms Morrissey. "And they should only say to parents, `this is what we think about this, what do you think?'"
When there is disagreement - as in the recent dispute over whether an eight-year-old and a five-year-old were old enough to cycle to school on their own - whose side is the law on? The simple answer is that school is school, and home is home, and that once a child leaves the premises the school no longer has responsibility, or authority. A headteacher can ban bicycles from the campus, but if a parent gives permission for their child to cycle to the gates the school has no right to stop them. Any attempt to do so could breach the United Nations Convention on the Rights of the Child.
"If the parents have given permission, that should be the end of it," says Richard Bird, legal specialist for the Association of School and College Leaders. "The school may give a view, but should do no more."
Often, a little tact is all that's needed. A useful rule of thumb is to imagine how you would feel if the boot was on the other foot and a parent was telling you how to deliver lessons or control the class. "You have to tread softly," says Mr Hegarty. "A strong relationship between parents and the school should allow both sides to express concerns in a constructive way."
WHAT TO DO
- Be careful not to patronise parents or impose your values on them.
- Often it is not what is said that causes offence, but the way a situation is handled.
- If you have concerns about a child's eating, sleeping or leisure habits, explain to parents how these things can affect academic progress. Encourage them to see the link between home and school.
- Schools' duty of care stops at the gate, but there is a statutory duty to promote child welfare. If you think a child is being abused or neglected, always inform the authorities.