Final answer:
Parents filed class action lawsuits against the Board to combat violations of equal education opportunities and to address segregation, as seen in the significant Brown v. Board of Education case.
Step-by-step explanation:
Parents filed class action lawsuits against the Board for various reasons related to educational policies and civil rights. One notable reason was the violation of students' right to equal education opportunities, as seen in the landmark case of Brown v. Board of Education. In this case, the Supreme Court ruled that segregated schools were inherently unequal and thus violated the 14th Amendment's equal protection clause.
Interest groups also use class action lawsuits to share costs and bring together plaintiffs with similar grievances, greatly impacting educational policy and civil rights advancements.