Members of the National Union of Teachers (NUT) are launching a campaign of action short of a strike, joining those in the NASUWT who are already taking action.
Industrial action by teachers over issues including pay, pensions and workload will be stepped up today amid warnings of an escalation in the coming months.
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Mr Kim has made two recent visits to China.
The study looked at the development of 422 children over the course of eight years.
The president said they will come into force if China refuses to change its practices.