I'm all for freedom of choice. I think that if people want to eat crap, drink crap and ruin their body's then that's up to them.

But there's a limit.

When one of my year sevens is bouncing off the wall in the afternoon and his excuse is drinking three cans of coke at dinner something has to be done. I urge everyone to take crowbars to the next vending machine they see, heckle newsagents and take drawing pins to bottles in supermarkets.

Not only would it make my Thursday afternoon post-PE lessons so much easier but it would also help fight childhood obesity. Something my year sevens also have views on. They think that bullying is good because by picking on fat people you can help them lose weight.

God help us.