Charters damage public schools by defunding them. 1 of 3 charter schools funded by the federal gov't never opens or closes soon after opening. In some states, the failed charters were even more than 1/3. The effect of charter school expansion is a serious threat to the finances of traditional public school districts. When students leave a public school system to attend a charter school they carry away money from the school district’s budget. Gordon Lafer: “To the casual observer, it's not obvious why charter schools should create any net costs at all for their home districts. To grasp why they do, it is necessary to understand the structural differences between the challenge of operating a single school—or even a local chain of schools—and that of a district-wide system operating 10s or100s of schools and charged with the legal responsibility to serve all students in the community.