Principals say every secondary school in the country needs one extra member of staff at work by the end of this month to get schools open in September.
The National Association of Principals and Deputy Principals says the job of drawing up timetables, preparing classrooms and planning rosters is too big for their members to complete in August with current staffing levels.
It is set to tell the Oireachtas COVID-19 committee later today that without this and more financial supports, they just will not be able to get ready in time.
The Association's president Alan Mongey says it will take all of August to prepare.
"There is a need for a financial package for schools to ensure they can implement the practices that were outlined in the HPSC guidance document that was issued to primary and post-primary schools.
"Additionally, each school requires the appointment or the reallocation of a staff member to assist with the implementation of the Covid-19 measures that will be required of the schools to safely return."
Mr Mongey said that bigger schools will require even more investment and staff.
