Illinois K-12 public school funding has long been characterized by large inter-district disparities in per-pupil expenditures. A primary reason for this characterization was the Illinois legislature's heavy reliance on local property tax within the various school funding formulas historically used to determine school revenues. The heavy reliance on local property taxes as the primary source of funding for Illinois schools has contributed to one of the largest funding gaps between the state's highest and lowest property wealth school districts in the United States. The heavy reliance on local property taxes has led to low property wealth school districts receiving a less than adequate share of education funding. The Illinois General Assembly's historical inability to adequately and equitably fund K-12 public education has prompted a number of lawsuits challenging the constitutionality of the State's methods for funding its public schools. While public school funding reform advocates have achieved victory under twenty-two state constitutions, courts have typically rejected plaintiffs' challenges to Illinois' methods for funding public schools and have directed plaintiffs to seek reform through the legislative process.As a result, reforming public school funding policy in Illinois is primarily a political process. While efforts to secure court-ordered school funding reform have been unsuccessful in Illinois, a nexus exists between legal challenges to the Illinois public school funding system and legislative reforms to Illinois public school funding policy after failed litigation. Since the 1970 Illinois Constitutional Convention, the state's public school funding policy has moved in apparent tandem with the various legal challenges to the methods used for funding public education. A review of nearly five decades of public school funding litigation and legislative transcripts reveals how plaintiffs may have directly influenced the discussion, formation, and enactment of subsequent school funding policy. Therefore, despite failing in the courts of law, evidence shows a strong connection in which plaintiffs have been tremendously successful in the court of public opinion, as their efforts have helped move Illinois legislators to modify the state's public school funding formula towards a more equitable and adequate financing system for all Illinois students through passage of the Evidence-Based Funding for Student Success Act of 2017. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]