Striking teachers have said the cost of living and heavy workloads are driving them out of the job they love.
Tomi Rowlands has decided to leave his teaching post and said some colleagues were using food banks to get by.
He is one of thousands of members of the National Education Union (NEU) striking on Wednesday over pay and school budgets.
The Welsh government said it would continue "constructive" meetings with unions to try to resolve the dispute.
Mr Rowlands, who will leave his job at Ysgol Bro Hyddgen in Machynlleth, Powys, in April, said he and his family were unable to afford to buy a bigger property.
