|(a) A public school employee must have the appropriate credentials for his or her current assignment specified in this chapter and in other rules of the State Board for Educator Certification (SBEC), unless the appropriate permit has been issued under Chapter 230, Subchapter F, of this title (relating to Permits). (b) The assignment requirements in this chapter apply to the holders of certificates issued on the basis of 1955, 1972, 1984, and 1987 Standards for Teacher Education as well as certificates issued on the basis of standards aligned with the Texas essential knowledge and skills curriculum, adopted by the State Board of Education, as specified in Chapter 233 of this title (relating to Categories of Classroom Teaching Certificates). (c) An elementary certificate may be appropriate for teaching high school students if the level of instruction is comparable to that in elementary grades. When such an assignment is made, course outlines must be maintained in the school district files. (d) Professional personnel employed in federally funded programs and innovative programs must have the qualifications and meet the assignment requirements specified in this chapter and in other rules of the SBEC. (e) The assignment requirements in this chapter apply to substitute teachers. If a school district must employ a substitute teacher who is not certified, a list of the substitute teachers shall be retained in the school district files.