Sec. 6. A contract entered into by a teacher and a school employer continues in force on the same terms and for the same wages, unless increased under IC 20-28-9-1.5, for the next school term following the date of the contract's termination unless one (1) of the following occurs:
(1) The school corporation refuses continuation of the contract under this chapter.
(2) The teacher delivers in person or by registered or certified mail to the school corporation the teacher's written resignation.
(3) The contract is replaced by another contract agreed to by the parties.