What is the test for a teacher to have a right to terminate their contract?

For the procedural rights of plaintiff under the due process clause of the Fourteenth Amendment to have been violated, she must have possessed a property interest as contemplated by the Fourteenth Amendment. Board of Regents v. Roth, 408 U.S. 564, 92 S.Ct. 2701, 33 L.Ed.2d 548 (1972). A teacher has a property interest in his or her job not only when he or she has formal tenure under an express provision of a statute or contract, but also when applicable rules or practices establish a "clearly implied promise of continued employment." Board of Regents v. Roth, id. at 576-77, 92 S.Ct. at 2709.