Teachers at two St Helens schools which cater for children with behavioural problems walked out last week in a row over sick pay.
Staff picketed outside Nugent House School in Billinge saying the school’s management had failed to meet their demands.
Teachers claim they are facing a 66 per cent drop in how long they can be off work with full or half pay.
The National Union of Teachers (NUT) claim some of the sick pay covers illnesses incurred at work - as the schools house some of the most troubled young people in the country.
Avis Gilmore, the NUT’s Executive Member for the region, called it a “cost-cutting exercise”.
She said her members faced some of the toughest pupils in the country.
If the situation is not resolved the special schools will face strike action again this week.
Mick Burrows, NASUWT National Executive Member for Merseyside, said the strike action was taken as a “matter of principle”.
Nugent House School is an independent school for 7-19 year-old boys with behavioural, emotional or social problems.
Strike action was also taken at St Catherine’s Secure Centre in St Helens. Both schools are run by Nugent Care, a North West charity.
A Nugent Care spokeswoman said: “Members of the NUT and NASUWT at two of Nugent Care’s establishments have voted to take part in strike action on six days throughout October. The strike is over a decision to alter the sick pay arrangements across the organisation.”