Your toilet bowl contains a U bend with water sitting in it. One end is open in the bathroom, the other opens on to your down stack pipe which used to be on the outside of the house but is usually inside nowadays. The down stack is open to the atmosphere for ventilation. When the wind blows across the down stack it changes the pressure in it. This pressure acts on the water in your toilet U bend and causes it to move up and down.
I suggest you try it Tilly and restrict yourself to one day a week and see how it goes. As well as doing day to day teaching cover you may be asked to do some small group/one-to-one intervention work in the run up to GCSEs which is enjoyable without the pressures of a full teacher role
I'll give it some thought. Thanks, factor. I need to do something. I'll ring around a few agencies and see what they need. One day a week sounds bearable.
Ozzy: Dogs seem to like drinking anything but 'clean' water. I don't know which one of ours is doing it but they keep drinking the little bit of water that collects in the handles of the sewage drain cover. To be quite honest I don't think I want to know which of the mucky pooches is doing it.