(1) Subject to paragraph (2), each rating shall be completed using the rating tools developed or approved under this subarticle.

(2) Professional employees who are considered satisfactory under section 1138.7¹ shall be rated no more than once annually. Professional employees who are considered unsatisfactory under section 1138.7 shall be rated at least annually. The first rating shall be calculated using the appropriate evaluation applicable to the employee. Any subsequent periodic rating shall be calculated as follows:

(3) One hundred percent of the semiannual rating of a temporary professional employee who serves as a classroom teacher or nonteaching professional shall be based on classroom observation and practice in the areas outlined under section 1138.3(a)(1), (b)(1) and (c).²

(4) Ratings shall be performed by or under the supervision of the chief school administrator or, if so directed by the chief school administrator, by an assistant administrator, a supervisor or a principal who has supervision over the work of the professional employee or temporary professional employee being rated, except that no unsatisfactory rating shall be valid unless approved by the chief school administrator.

(5) No employee shall be dismissed for unsatisfactory teaching performance under section 1122³ unless the employee has been provided a completed rating tool provided for under this subarticle, which includes a description based upon classroom observations of deficiencies in practice supported by detailed anecdotal records that justify the unsatisfactory rating.