It is well known that Pennsylvania's K-12 schools are inadequately and inequitably funded. But the extent of the problem is not fully understood. This paper uses new data and methods to demonstrate just how unfair--and in fact, morally unsustainable--the funding of elementary and secondary education is in the Commonwealth. It shows that the proposal put forward in Governor Wolf's 2021-2022 Executive Budget, or something much like it, is a necessary first step toward reforming the shameful way K-12 schools in Pennsylvania are funded. The origins of the deep inadequacy and inequity in school funding go back decades. For the purposes of this paper, the source of the problem is divided into two parts. First, the state share of funding of K-12 schools has been declining since the early 1970s under Democratic and Republican governors--but it is mostly a result of Republican control of the General Assembly. Second, measuring the adequacy of funding by looking at the gap in per-student spending in school districts between what they spent in 2019 and what they should spend according to a 2020 update to the "Costing-Out Study" carried out by Augenblick, Palaich and Associates (APA) at the request of the State Board of Education pursuant to the bipartisan Act 114 of July 2005. Governor Wolf's proposal for K-12 education funding for the fiscal year beginning July 1, 2021, is a major step forward in providing adequate and equitable funding for Pennsylvania's schools. However, it does not close the funding gap for most schools. Nor does it eliminate all of the economic, racial, and ethnicity-based inequities in school funding.