A multi-storey extension to Virginia College will be "welcome news for all parents and pupils".
Nine classrooms, three science labs and special education facilities will be constructed as part of the investment.
Earlier this afternoon, the Department of Education approved the multi-million euro submission by CMETB.
The extension will see the development of nine general classrooms, three science labs, two special education teacher rooms, two special educational needs classrooms as well as two prep areas.
Praising the staff of Virginia College and CMETB, Local Minister Heather Humphreys welcomed the news saying investing in school buildings is more important than ever.
She added that it'll be "hugely welcome news for all parents and pupils involved, as they get ready for our schools to return".
Fianna Fail TD Brendan Smith also welcomed the development.
In June, similar large-scale extensions had been announced for Beech Hill College in Monaghan town and Our Lady's Secondary School in Castleblayney.