Guernsey's "new model" of secondary education will cost £157m, according to the Education Committee.
The Committee has applied to the States for the funding, which is £30m less than initial projections.
A one-school, two-site plan was agreed in the States in October, which would turn four separate schools into a single, multi-site school.
As well as the new school structure, the model proposes significant changes to the education system.
According to Deputy Matt Fallaize equality of opportunity will be at the "heart" of the model .
Deputy Fallaize described the current education system as having inequality "built" into it.
"Students have different opportunities depending entirely on their 11+ results or where in the island they live." he said.
To address the issue the proposals are intended to expand access to a more varied curriculum as well as offer better facilities for all students.
A breakdown of the total cost includes £69m for redeveloping St Sampson's High and Les Beaucamps High, up to £22.4m for Mare de Carteret Primary School and £47m for the Guernsey Institute at Les Ozouets campus.
The institute will integrate several institutions of higher learning including the College of Further Education, the Institute of Health & Social Care Studies and the GTA University Centre.