Head teachers believe inspections can be damaging
Head teachers meeting in Brighton have condemned what they call the "corrosive effect" of England's school inspection system.
At the annual conference of the National Association of Head Teachers, heads and deputies said inspections had led to high stakes, with some heads driven to despair.
Delegates backed a motion calling on the union to come up with a "battle plan" to combat what they called "this scourge of true education".
They complained schools were being given "arbitrary labels" and put into "meaningless and soul-destroying" categories.
One delegate, Tony Roberts from Lancashire, said inspections were placing head teachers under too much pressure and that Ofsted was not accountable.
Proposing the motion which called for a battle plan, he said: "We are accountable as a profession, but we have the right to be judged by a system which is fair".
For Cheryl Bould, from Wolverhampton, the problem is that inspections, she says, do not take the "contexural picture" into account
Katrina Williams, from East Ridings, said her school had been inspected three times in a year - once for a full Ofsted inspection, once for a new subject-only inspection and once by the diocese, because hers is a faith school
The NAHT's leadership criticises Ofsted inspections for what it believes is over-reliance on data, such as the Sats tests and data known as "contextural value added" - a measure of progress pupils make throughout their time in school.
They argue that this kind of data is not reliable.
Gail Larkham, a head from Surrey, said the CVA scores, as they are known, could not show improvements in very bright children because primary school Sats tests only measure up to a certain level (level 5).