There are calls for a new school building to be completed for Scoil Mhuire in Carrick-on-Shannon within the next five years.
The national school's pupil numbers have almost doubled in the past 10 years, with 498 children enrolled for the forthcoming year.
The school is spread over two campuses, and some classes are held in prefabs and subdivided rooms.
Principal Caroline Healy says the department is aware of the need for a new school building - but she wants greater action.
Louise Murray is the community representative on the board of management, and her two children recently graduated from the school.
She also wants firmer action from the department.