Del. Code tit. 14, § 1503

No contract for public school purposes that is predicated on the availability of state funds shall be made to extend beyond the fiscal year covered by the current appropriation of the General Assembly in effect at the time of the making of such contract, unless all of the funds required to satisfy the obligation are available for encumbrance, or a cancellation provision should funds not be subsequently appropriated is included in the original contract. This provision does not apply to contracts involving the expenditure of moneys raised by bond issues or advance purchase orders for instructional materials duly authorized by the Secretary of Finance.