Academies are publicly-funded independent schools for pupils of all abilities, established by sponsors from business, faith or voluntary groups working in partnership with central Government and local education partners. The independent status of academies is intended to allow flexibility in their curriculum, staffing, governance and working arrangements when compared to conventional local authority schools.
Academies receive grant-funding directly from central Government. The amount received is deducted from the grant allocated to the local authority responsible for education in the area that the school is located.


See:

http://www.standards.dcsf.gov.uk/academies/