So what does the California Education Code state about grading practices?
49066. (a) When grades are given for any course of instruction taught in a school district, the grade given to each pupil shall be the grade determined by the teacher of the course and the determination of the pupil's grade by the teacher, in the absence of clerical or mechanical mistake, fraud, bad faith, or incompetency, shall be final. (b) The governing board of the school district and the superintendent of such district shall not order a pupil's grade to be changed unless the teacher who determined such grade is, to the extent practicable, given an opportunity to state orally, in writing, or both, the reasons for which such grade was given and is, to the extent practicable, included in all discussions relating to the changing of such grade. (c) No grade of a pupil participating in a physical education class, however, may be adversely affected due to the fact that the pupil does not wear standardized physical education apparel where the failure to wear such apparel arises from circumstances beyond the control of the pupil.
49067. (a) The governing board of each school district shall prescribe regulations requiring the evaluation of each pupil's achievement for each marking period and requiring a conference with, or a written report to, the parent of each pupil whenever it becomes evident to the teacher that the pupil is in danger of failing a course. The refusal of the parent to attend the conference, or to respond to the written report, shall not preclude failing the pupil at the end of the grading period. (b) The governing board of any school district may adopt regulations authorizing a teacher to assign a failing grade to any pupil whose absences from the teacher's class that are not excused pursuant to Section 48205 equal or exceed a maximum number which shall be specified by the board. Regulations adopted pursuant to this subdivision shall include, but not be limited to, the following: (1) A reasonable opportunity for the pupil or the pupil's parent or guardian to explain the absences. (2) A method for identification in the pupil's record of the failing grades assigned to the pupil on the basis of excessive unexcused absences. (c) Notwithstanding the provisions of subdivision (a) of Section 49061, the provisions of this section shall apply to the parent or guardian of any pupil without regard to the age of the pupil.