Hundreds of non-regular workers at Seoul schools launched a two-day strike Thursday, including many working in school cafeterias.

Around 2,500 members of the Seoul branch of a coalition representing non-regular school workers were expected to join the walkout to demand changes to their retirement pension system.

While many are cafeteria workers who prepare meals for students, the group also includes administrative staff members and child care workers responsible for after-hours programs.

The striking workers demand changes to their retirement pensions, seeking to replace the current defined contribution plan with a defined benefit plan that offers better income stability.

Under a defined contribution plan, the pension is based on how much the employee and employer pay in, and under a defined benefit plan it is based on the worker’s salary and duration of employment.

The Seoul Metropolitan Office of Education is refusing the proposal, citing cost worries. Instead it has offered a compromise package, but said details of its proposed plan had not yet been decided.

Two weeks earlier, 6,000 care workers affiliated with the school workers’ union staged a one-day nationwide walkout in protest of proposed changes to school child care management and to their employment status, causing a disruption in child care services.

By Ko Jun-tae (ko.juntae@heraldcorp.com)