UK Nationwide testing boycott

...has gotten enough teachers on board that it's working:

The estimate of the amount of disruption caused by a boycott of the tests - in maths and English - increased yesterday. Christine Blower, general secretary of the National Union of Teachers, said that the number of schools backing the boycott ranged from 30 per cent to 75 per cent from local authority to local authority. Overall, about half of the 17,000 schools due to sit the tests are set to abandon them...
The NUT - along with the National Association of Head Teachers - has voted in favour of boycotting the tests because they believe the importance placed on them - with performance tables based on their results - has forced schools to teach to the tests at the expense of the broader curriculum...