There is a tide in the affairs of men and adolescent children. Like the seventh wave which dashes the boat against the hidden reef, a generation of horrors can take you unawares. Just when you thought all was going swimmingly in the ocean of learning (now there is a melange of metaphor)…

The word first arrives as a rumour. A teacher will be talking to another from one of the feeder schools. Something wicked this way comes.

Fears will be confirmed in orientation week when Year 7 teachers will enter the common room with the haunted look of border guards reporting the return of the Visigoths. All Rome shudders at the prospect. And just as Romans came to dread the name of Alaric so in time will we come to shudder at the mention of Costas or Maddy or Tyson or Cody.

How to account for this generational anomaly? It sends you trawling through the almanacs. Was it West Coast winning the first premiership by a non-Victorian team which inspired a spate of angry rutting among the breeding footy fans in 1992? That would certainly account for the current Year 10s. But what was so traumatic about 1997? Very possibly it is just a case of statistical coincidence. Bad seeds randomly spawned in the same geographic sampling. It is a puzzle and a worry.

As the rotten Year 7s become rotten Year 8s and (malign metamorphosis) rotten Year 9s until finally they are the perfect antithesis of role models in their senior years, you learn to scan each year’s coming teaching allotments to see if you have drawn the short straw and go down on your knees to the timetabling gods should the angel of death pass over you.

And as the rotten Year 7 passes through the school system like a bad oyster, you marvel at how inventive children can be in their cruelty. The young are no longer content to place upturned drawing pins on seats or shove rulers up bums or (and we’re going right back here) dip ponytails into inkwells. It makes you feel your age when reports come through of cyber bullying and nude snaps circulating through the network like a virus. This is what happens when you put a computer mouse in the hands of a toddler. Or believe fondly that a mobile phone is an essential item for “safety”.

So for six long years you sit out the bad times and breathe freely only once the bad bunch has been loosed upon the world. But don’t get too comfortable. Soon enough on the horizon will appear the outline of spears and the totems of strange gods demanding mayhem and the blood of the vanquished.