Using the budget and enrollment figures from the article (though PDE data indicate that the district received almost $100 million in revenue in 2004-05), I calculate that charter schools spend about $9,700 per pupil, while district schools have $13,882 for each pupil they are responsible for educating. Add to the the estimated reimbursement to the district for charter payments of $7 million from the state, and per-pupil spending for students in the district-run schools increases to $15,451.
Thus, charter school enrollment increased per-pupil spending in district schools by about $3,200. This should allow for reduced class size, increase focus on individual students, and improvement in the educational offerings – but the school district must make do with less total money to spend. The question is whether education money should be used for educating students or to pay staff, administrators, and to build buildings.