A number of subjects are to be taught through Irish at 19 schools and early years centres.
It is part of a new project to promote the teaching of the language.
The three year Content and Language Integrated Learning (CLIL) pilot will see PE and other subjects taught to children across different age groups as Gaeilge.
The schools were selected on the basis of criteria set out in the application process - including the size of the school, location to support clustering and ongoing engagement between schools and experience of using CLIL.
The first year of the project will help to inform the Department of Education on the development of the programme - including assessment and resources.
A project team will then assess each of the settings and schools to identify its level of preparedness for the project, and what further supports they may need.
The theme of 'communicating' will be taught through Irish in early years settings.
In the primary and post-primary schools, three subjects will be taught through Irish - including PE.
The other two subjects have yet to be finalised but may include visual arts, maths, science, business, geography, SPHE or CSPE.
Some subjects may be taken through Irish for a full class or part of a class, every day or once a week.
Announcing the project, Education Minister Joe McHugh said: "I am delighted that this exciting project is underway.
"The standard and enthusiasm evident in many of the applications meant that we could arrange a pilot that is bigger than originally envisaged."
"Our talented teachers have seized this opportunity to help promote the language in a novel way.
"We will have a lot to learn from the project over the course of the next three years and it will improve all the time.
"I am confident that by introducing Irish across different subjects in schools then we will make it more relevant and help young people connect with it in a new and better way."
This three-year project started in September this year.
The following schools and early years centres have been selected for the initial phase of the project:
Early Years:
Teach Abhaile pre-school, Ennis, Co Clare
Mounthawk Montessori, Tralee, Co Kerry
High Hopes Montessori, Harolds Cross, Dublin
Roots and Wings, Donabate, Co Dublin
Fairytales day care, Milford, Co Donegal,
Teach Leanbh, Ballinalee, Co Longford.
Primary:
Holy Family Senior NS, Ennis, Co Clare
St. Olivers NS, Killarney, Co Kerry
St. Mary's NS, Donnybrook, Dublin 4
Scoil Réalt na Mara, Skerries, Co Dublin
SN Naomh Colmcille, Kilmacrennan, Co Donegal
St. Colmcille's SNS, Kells, Co Meath
St. Comán's Wood PS, Roscommon
Post-primary:
Colaiste Fionnchua, Mitchelstown, Co Cork
Millstreet Community School, Millstreet, Co Cork
Presentation Secondary School, Castleisland, Co Kerry
St. Muredach's College, Ballina, Co Mayo
St. Joseph's, Mullingar, Co Westmeath
Clonaslee College, Co Laois
