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Principal: Schools being asked to do parents' role
Meeting the parents of their children's friends gave people an idea of their values and parenting style.
"You knew what they looked like; you could say hi; you probably had a good idea of what they valued and how they parented.
"You could also make judgement calls on the connection of their values to yours.
"Now, I bet you don't have those connections. And your distance from your son's influences is rapidly getting wider.
"If you want to know why, have a look at his smartphone."
Hall said many pupils developed a sense of what was acceptable behaviour from seeing how other people behaved via their cellphones.
"Now, through his smartphone, your son's influences are not only people and adults you have never met, but also people who don't even live in the same hemisphere.
"I am no expert, but I would think that it is not the people you know that encourage your child to send or share inappropriate images via that smartphone.
"As a school, we have never said a phone is an appropriate learning device.
"Teachers let students use them, mainly because they have little choice. But if all smartphones were left at home, we wouldn't cry."
A solution would be to find out who your child's close influences were, the children they mixed with and who called them up.
While that would concern some parents because they might incur the wrath of their children and feel "uncool", they had to be realistic.
"You stopped being cool when you became a parent and if you believe you didn't, you are kidding yourself," Hall said.
"The parents of boarders in our school do this much better. In the country areas people stop and talk, they converse, they expect that you want to talk to them.
"In town, we rush for the sake of rushing.
"Stop, talk, listen. It will be good for your health too."
If a parent did not know who their child's influences were, it would be difficult for the parent to be the leading influence in their child's life.
"And this to me is where it is getting harder for schools. We are expected to be the leading influences in [the child's] life.
"I believe this is a significant issue, but as a community it is easily and quickly fixed.
"We just have to go back to acting like a community.
"We just have to acknowledge it first and then we have to put together some clear strategies to defeat it.
"It's something we need to work through together."