Except as provided under this section, school districts and public charter schools must not provide any course or otherwise carry out any of its programs or activities separately on the basis of sex, race, creed, religion, color, national origin, honorably discharged veteran or military status, sexual orientation, gender expression, gender identity, the presence of any sensory, mental, or physical disability, or the use of a trained dog guide or service animal or require or refuse participation therein by any of its students on such basis. This section does not prohibit:

(1) The grouping of students in physical education classes and activities by demonstrated ability as assessed by objective standards of individual performance developed and applied without regard to sex. Where use of a single standard of measuring skill or progress in a physical education class has an adverse effect on members of one sex, the school district or public charter school must promptly implement appropriate standards that do not have such effect;

(2) The separation of students by sex within physical education classes or activities offered for students if:

(a) It can be shown under the factual circumstances involved in the particular case that maintaining a separate physical education class or activity for boys and girls is the best method of providing both sexes with an equal opportunity to participate in the class or activity; and

(b) The separated classes or activities are substantially equal;

(3) The separation of students by sex for classes or portions of classes that deal primarily with human sexuality;

(4) Classes and activities with requirements based on vocal range or quality, which may result in a chorus or choruses of one or predominantly one sex; and

(5) Classes, courses, or placement of students based on the student's individual language skill development or based on the student's needs as identified in the student's individualized education program under the Individuals with Disabilities Education Act.