Here’s what should be in the plan (from CDE):

“LEAs should begin the plan revision with an analysis of the reason(s) for PI identification. The LEA should conduct an in-depth analysis of its achievement data patterns and current educational practices to determine whether it obtained PI status because of the achievement or participation rate of a single group, or because of multiple low achievement trends across grade spans and/or subject areas. The state has developed several analytic tools (listed below) to inform the LEA planning process. Use of these tools is required to ensure that the needs of all students are addressed. (California Education Code Section 52055.57[6]) LEAs should begin implementing the plans outlined in the LEA Plan Addendum immediately upon its completion and local board approval.

Content Requirements for LEA Plan Addendum
According to provisions in ESEA, the LEA Plan Addendum is required to meet all requirements specified in ESEA Section 1116(c)(7)(A)(i) through (viii):

Address the fundamental teaching and learning needs in the schools of the LEA and the specific academic problems of low-achieving students, including a determination of why the prior LEA Plan failed to bring about increased student achievement.
Identify actions that have the greatest likelihood of improving the achievement of students in meeting state standards.
Incorporate scientifically based research strategies that strengthen the core academic program in schools served by the LEA.
Include specific, measurable achievement goals and targets for all students and subgroups, addressing all elements of Adequate Yearly Progress (AYP).
Address the professional development needs of the instructional staff. Indicate that the LEA will dedicate not less than 10 percent of the LEA Title I allocation for high quality professional development.
Identify how technical assistance will be obtained to support implementation of the LEA Plan revisions (e.g., Senate Bill 472 training, Assembly Bill 430 training, county office support, and work with such organizations as the California School Boards Association, California Teachers Association, Association of California School Administrators, California Federation of Teachers, Parent Teacher Association, institutions of higher education, and public and private organizations).
Incorporate, as appropriate, learning activities before school, after school, during the summer, and during an extension of the school year.
Include strategies to promote effective parental involvement in the school.”

The school board needs to approve the plan and then the district is supposed to begin implementing it “expeditiously.”