Let’s look at a real example of charter schools in an poor urban area with rotten schools, say, Camden. Here’s the sorry stats for Camden High School: 23.8% of high schoolers pass the High School Proficiency Assessment (which Education Commissioner Lucille Davy has labeled an 8th grade level test); average SAT scores are 344 for Math and 346 for Verbal; no Advanced Placement courses are offered; 49.9% of kids graduate; fewer than 20% go on to 2 or 4-year colleges.

There are two charter schools in Camden that accept high school kids: LEAP Academy University Charter School and Camden Academy Charter School. (836 kids are on waiting lists for the two schools, by the way.) At LEAP, 57.4% pass the HSPA; average SAT scores are (not much better) 383 for Math and 375 for Verbal; 4 A.P. classes are offered; 100% of kids graduate; 96% go on to 2 or 4-year colleges. At Camden Academy 68.7% pass the HSPA; average SAT scores are 383 for Math and 375 for Verbal; 6 A.P. courses are offered; 100% of kids graduate; 90.7% go on to 2 or 4-year colleges. (DOE data here.)

Here’s the kicker (which should have come up at the debate and didn’t): total cost per pupil at Camden’s traditional public high schools is $15,407. Total cost per pupil at LEAP is $11,029 and at Camden Academy it’s $12,501.

You can play with the numbers any way you want. Four years at Camden High costs taxpayers $62.6K per kid. Four years at LEAP is $44.1K and four years at Camden Academy is $50K. Total enrollment of all high school students in Camden, whether public or charter school students, is 3451 children. At $12,501 per year per student (we’ll take the more expensive charter for convenience) the tab is $43,140,951. Put all those kids in the traditional public schools and the bill is $53,169,557. In other words, if all the high schoolers in Camden went to charter school, we’d save $10 million dollars per year.

One could argue that it’s not all about money. One could argue that charter schools “cream off” the more easily managed students (though Professor Carolyn Hoxby’s recent study dispells that notion). Still, 10 million dollars is 10 million dollars.