(a) The cost of the Foundation School Program for a school district is the total sum of:
(1) the sum of the tier one allotments and other funding as follows:
(A) the basic allotment under Subchapter B;
(B) the student-based allotments under Subchapter C; and
(C) the additional funding under Subchapter D; and
(2) the tier two allotment under Subchapter E.
(b) The sum of the Foundation School Program maintenance and operations costs for all accredited school districts in this state constitutes the total maintenance and operations cost of the Foundation School Program.

(c) The program shall be financed by:
(1) state available school funds distributed in accordance with the law;
(2) ad valorem tax revenue generated by local school district effort; and
(3) state funds appropriated for the purposes of public school education and allocated to each district in an amount sufficient to finance the cost of each district’s Foundation School Program not covered by other funds specified in this subsection.