Q: Would districts that adopt the proposed framework be violating the law?

A:  In a few short words: depending on its implementation in a school district, potentially yes.  Note that the following should not be construed or relied upon as legal advice; you should consult a lawyer for a legal opinion.

In reality, in many things, kids are at different levels, also in the study of mathematics.  Some are more goal-oriented and have a genuine passion.  Others may find math less interesting.  For whatever reason, kids have different levels of interest and have different natural rates of progression through mathematics.  The CAMF seeks to equalize outcomes by forcing all students to be in the same classroom at the same level and rate of progress.  A major reason for this approach is to create “equity.”  Not only is this unnatural, it may actually be illegal, depending on how it is implemented.  In some school districts that have already implemented de-tracking and put all students in a grade into the same undifferentiated classroom, unnatural force must be applied to slow down kids who have a high appetite for math.  Policies have been put in place to either make it extremely difficult for a student to advance to the next level, i.e. “skipping” a level, or even to make it non-negotiably impossible.  Section 1 of SB359, which has become law as The Math Placement Act of 2015, aka EDC § 51224.7, states:

SB 359(1)(c) The most egregious examples of mathematics misplacement occur with successful pupils and, disproportionately, with successful pupils of color. These successful pupils are achieving a grade of “B” or better, or are testing at proficient or even advanced proficiency on state assessments. Nevertheless, they are held back to repeat 8th grade mathematics coursework rather than advancing to the next course in the recommended mathematics course sequence.

And (excerpted):

51224.7 (a) This act shall be known, and may be cited, as the California Mathematics Placement Act of 2015.
(b) Governing boards or bodies of local educational agencies that serve pupils entering grade 9 and that have not adopted a fair, objective, and transparent mathematics placement policy, as described in paragraphs (1) to (5), inclusive, as of January 1, 2016, shall, before the beginning of the 2016–17 school year, develop and adopt, in a regularly scheduled public meeting, a fair, objective, and transparent mathematics placement policy for pupils entering grade 9 that does all of the following:
(1) Systematically takes multiple objective academic measures of pupil performance into consideration. For purposes of this paragraph, “objective academic measures” means measures, such as statewide mathematics assessments, including interim and summative assessments authorized pursuant to Section 60640, placement tests that are aligned to state-adopted content standards in mathematics, classroom assignment and grades, and report cards.
(2) Includes at least one placement checkpoint within the first month of the school year to ensure accurate placement and permit reevaluation of individual pupil progress.
(3) Requires examination of aggregate pupil placement data annually to ensure that pupils who are qualified to progress in mathematics courses based on their performance on objective academic measures selected for inclusion in the policy pursuant to paragraph (1) are not held back in a disproportionate manner on the basis of their race, ethnicity, gender, or socioeconomic background. The local educational agency shall report the aggregate results of this examination to the governing board or body of the local educational agency.
(4) Offers clear and timely recourse for each pupil and his or her parent or legal guardian who questions the pupil’s placement.

Clearly, this language is at direct odds with the placement policies in school districts already implementing rigid de-tracking policies.  The intent of the Math Placement Act is precisely to ensure equity in placement of successful students, specifically calling out disproportional misplacement of students of color  The CAMF seeks to eliminate objective measures of achievement in mathematics in order to be intentionally unable to identify high achievers, also directly at odds with the Math Placement Act.

As the overarching intent of the proposed CAMF is to bring equity by equality of outcome, the Math Placement Act seeks to bring equity by the exact opposite philosophy to ensure equal opportunity.  Lawsuits are already underway claiming that school districts forcibly enforcing de-tracking are in violation of the law.

Furthermore, as many students take external math programs to compensate for the loss of learning enforced by rigid de-tracking policies, some districts have additionally implemented policies that deny advancement regardless of success in external programs.  For a student to take external classes to achieve progress would defeat the policy and intent of yoking all students together.  Therefore some districts refuse to acknowledge successful completion of external classes and force students to repeat the class alongside their de-tracked peers.  This is a horrible situation where the student has to waste a year repeating the class without learning anything. Furthermore, these policies may be illegal as provided by EDC § 51228.2 (excerpted):

51228.2 (a) Commencing with the 2016-17 school year, except as provided in subdivision (d), a school district maintaining any of grades 9 to 12, inclusive, shall not assign a pupil enrolled in any of grades 9 to 12, inclusive, in a school in the school district to a course that the pupil has previously completed and received a grade determined by the school district to be sufficient to satisfy the requirements and prerequisites for admission to the California public institutions of postsecondary education and the minimum requirements for receiving a diploma of graduation from high school established in this article, unless either of the following applies:

(1) The course has been designed to be taken more than once because pupils are exposed to a new curriculum year to year and are therefore expected to derive educational value from taking the course again.

(2) For any course that has not been designed to be taken more than once, all of the following conditions are satisfied:

(A) A pupil is assigned to the course only if the pupil or, for a pupil who has not reached the age of majority, the pupil's parent, guardian, or educational rights holder has consented in writing to the assignment for the purpose of improving a lower grade.

(B) A school official has determined that the pupil will benefit from being assigned to the course period.

(C) The principal or assistant principal of the school has stated in a written document to be maintained at the school that, for the relevant school year, no pupils are assigned to those classes unless the school has met the conditions specified in subparagraphs (A) and (B).

(b) Under no circumstances shall a school district assign a pupil enrolled in any of grades 9 to 12, inclusive, in a school in the school district to a course that the pupil has previously completed and received a grade determined by the school district to be sufficient to satisfy the requirements and prerequisites for admission to the California public institutions of postsecondary education and the minimum requirements for receiving a diploma of graduation from high school established in this article because there are not sufficient curricular course offerings for the pupil to take during the relevant period of the designated schoolday.

For those students who have successfully completed a UC-approved class, it is clearly illegal policy to force them to repeat the class.  Yet, in the spirit of the CAMF and for the purposes of disallowing escaping de-tracking policies, some school districts are indeed already breaking the law in order to implement the CAMF recommendations.