In addition to the words and terms defined in §23.1 of this chapter (relating to Definitions), the following words and terms, when used in this subchapter, shall have the following meanings, unless the context clearly indicates otherwise:(1) Certified Educator--A person who has completed all requirements for a standard teaching certificate in the State of Texas. A person holding a probationary certificate, temporary classroom assignment permit, emergency permit, or a nonrenewable permit is not considered a certified educator. The term does not include a teacher's aide or a full-time administrator.(2) Public School--A school in a Texas school district or a public charter school authorized to operate under Texas Education Code, Chapter 12.(3) Service Period--A period of service of at least 9 months of a 12-month academic year.(4) Shortage Communities--Texas public schools identified annually by the Texas Commissioner of Education, or his/her designee, whose percentage of economically disadvantaged students is higher than the statewide average percentage of students receiving free or reduced cost lunches.(5) Shortage Teaching Fields--Subjects identified annually by the Texas Commissioner of Education, or his/her designee, as having a critical shortage of teachers.(6) Teaching full-time--Teaching at least four hours each day performing instructional duties as a full-time employee of a Texas public school district.