S.C. Code § 59-41-40
It shall be a prerequisite to the grant above permitted that the local school district in which the school child resides make available a grant of local funds to such school child and to that end the trustees of each school district within the State are hereby authorized to appropriate funds in addition to the State scholarship grants provided for in Section 59-41-20 in such amount that is equal to the per pupil cost to the school district exclusive of all State funds received for such purposes. The trustees of each school district are authorized to levy taxes where the school district has the power to tax, to raise funds for the payment of such local supplements to the State scholarship grants. The State Board of Education shall render such assistance to the trustees as may be necessary to determine annual per pupil expenditures of the school district for the purpose of fixing the amount of any supplement to be paid under this section.
S.C. Code § 59-41-40