A contract for employment of a teacher or administrator authorized under section 79-818 shall contain (1) a provision by which the employed person affirms that he or she holds or will hold, at the beginning of the term of the contract, a valid certificate properly registered with the school district and that he or she is not under contract with another school board of a school district in this state and (2) a provision that there shall be no penalty for release from the contract.
Neb. Rev. Stat. §§ 79-819