As stated from Greatschools.org
The school site council is a group of teachers, parents , classified employees, and students (at the high school level) that works with the principal to develop, review and evaluate school improvement programs and school budgets.
Over the course of a year, a typical council might consider the goals of the school or district and then work with the principal to evaluate the school’s progress toward those goals. In this evaluation, the council might consider school test scores, attendance and discipline records, parent surveys and input from students.
School site council members don’t just represent their own interests. They have an obligation to make decisions that will best serve the whole school community. In fact, many site councils are specifically charged with finding ways to close gaps in achievement between groups of students.
If you are interested in school policy or budgets, you might enjoy serving on your school’s site council. To find out more about what your school site council does, attend a meeting or talk to the school principal. If you would like to participate on the council, call the school secretary to find out how the selection process works at your school.