Within Subdistrict A, any floor space designated for use as a school shall be exempted from the definition of floor area for the purposes of calculating the permitted floor area ratio for community facility uses and the total maximum floor area ratio of the zoning lot, provided that such school is either:

1. a public school, subject to the jurisdiction of the New York City Department of Education, pursuant to an agreement accepted by the School Construction Authority; or
2. a charter school, subject to the New York State Education Law, pursuant to an agreement with a charter school organization.