One day last month, an Evanston resident named Zoe Zolbrod came across an e-mail blast from the office of U.S. senator Mark Kirk with the headline, "9 of the top Ten High Schools in Chicago are Charter Schools."

Kirk's declaration took Zolbrod by surprise. "I don't pretend to be an expert," says Zolbrod, an editor at a publishing house. "But I do know that nine out of the top ten performing high schools in Chicago are definitely not charters."

In this case, you don't have to be an expert—you, like me, can just go to the website of the state board of education to see exactly which schools are doing how well in the great test-taking game.

It turns out that Zolbrod was right: nine out of the ten top-scoring high schools in Chicago are not charters.

In fact, if you use ACT scores as the measurement, as Senator Kirk did, you'll discover that none of the top ten public high schools in Chicago is a charter.

That's none—as in zero.

Now, before I go further, let me say this: I'm usually the last person in the world to start throwing test scores around. I don't think much of using a test to try to measure how schools, teachers, parents, and especially children are progressing.

But since Senator Kirk raised the subject . . .

The highest-ranking charter, Chicago Virtual, ranks 11th. Its average ACT score for the 2010 to 2011 school year was 20.1—well below the 29.2 average at Northside College Prep, which tops the list.

That's not all. It seems that only two of the top 20 are charters—Noble Street Charter also cracks the top 20 list with 19.9.

As a matter of fact, nine of the 13 charter high schools that reported ACT scores were below the system's 17.7 average.

In short, most regular high schools in Chicago—with their unionized teachers—are beating the charters, at least when it comes to ACT scores. But don't hold your breath waiting for Senator Kirk to send that out in an e-mail blast.

To be fair, Kirk wasn't the first politician around here to screw up on this issue. During the mayoral campaign last winter, Rahm Emanuel asserted that besides Northside and Walter Payton, two public magnet schools, "the seven best-performing high schools are all charters."

That's not any more true than what Kirk said. If anything, it's a more egregious falsehood than Kirk's. After all, Kirk's connection to Chicago is largely limited to using it as a place to raise money when he's not using it as a whipping boy to win over Chicago-hating voters from downstate and the suburbs.

Emanuel, on the other hand, was running for mayor. So you'd think he'd at least know a few of the basics about the schools he was promising to reform.

But Kirk and Emanuel look at charters much the same way. By puffing them up, the two politicians can employ the charters as hammers to whack away at the teachers union. It's part of a larger campaign to attribute everything that's wrong with public education today to "bad" teachers who keep their jobs thanks to a teachers union that doesn't care about kids.

Zolbrod, the Evanston resident, wasn't so easily persuaded. After reading Kirk's e-mail message, she called the senator's office for an explanation. Zolbrod wound up talking to an aide.

According to Zolbrod, the conversation went like this:

Zoe: How can you say that nine out of the top ten schools are charters? Aide: That statement refers to the top nonselective Chicago high schools. Zoe: But the e-mail doesn't say anything about nonselective high schools. Aide: It says it on the accompanying chart. Zoe: But there is no accompanying chart. Aide: The chart's online.

Having read the e-mail, I can assure you that it doesn't include an accompanying chart. It doesn't refer readers to a chart on Kirk's website, but I went to the website anyway. I couldn't find a chart on it.

There is, however, a link to a speech given by Kirk in which he calls for more federal funding for charters on the grounds that charters constitute "eight out of the top ten nonselective schools" in Chicago. And by nonselective, Kirk says he means schools "that take everyone."

And that brings us to a whole new subject: selective-enrollment schools.

When they talk about such schools, Kirk and his aide are clearly referring to the eight Chicago high schools that limit enrollment to the highest test takers (Northside, Payton, Young, Jones, Lane, Brooks, Lindblom, and King)—all of which are in the top ten in ACT scores.

But why remove them from the ACT rankings? It's not like charter school grads won't have to compete against selective-enrollment grads for college, graduate school, and jobs. Taking these schools off the list is like saying, "Eight of the state's top ten basketball teams are charters, except for the 50 other schools that score more points and win more games."

For that matter, charters aren't open-enrollment schools either: despite what Kirk says, they don't take everyone. They limit their rolls to kids whose parents tend to be involved in their education, starting with going through the application process.

That's different from neighborhood schools, which have to open their doors to every kid who lives within their attendance boundaries, whether the parents are active in their lives or AWOL.

And just about everyone in the school reform debate—from unionized educators to charter advocates—agrees that parental involvement is critically important in determining how a child fares in school.

Plus, as I've reported before, charters get to be more choosy about which kids they keep on the rolls—and the neighborhood schools have to take whomever the charters kick out.

So it's really no less fair to compare charters to Northside and Payton than to compare them with neighborhood schools, since they're really all operating on different sets of rules.

Still, for the sake of argument, let's play charters' advocate and take the eight selective-enrollment high schools out of the mix.

Even then, the charters don't do all that well: they account for only two of the top ten—and five of the top 20—nonselective-enrollment high schools in Chicago.

So how does Kirk manage to fit eight charters into his top ten list?

The senator's press aide sent me to a report on the Illinois Network of Charter Schools website. The report assembles a ranking that not only eliminates the eight selective-enrollment schools, but 12 other schools that require parents to fill out an application for admission—even though parents also have to fill out an application for admission to the charter schools.

For some reason a song by the great Joe South comes to mind: "Oh, the games people play now / Every night and every day now / Never meaning what they say now / Never saying what they mean . . ."

The bottom line: you can put together a list in which charters are eight of the top ten schools. Hell, try hard enough and you could probably put together a list in which the top ten schools are all charters.

Of course, that list—like the ones put together by Kirk and Emanuel—would grossly distort the reality confronting Chicago's public schools.

And that reality is this: no one, charter boosters included, has figured out a way to eradicate the disparities between the kids from the most dysfunctional neighborhoods and the kids from the wealthier and more stable parts of town.

At the very least, anyone who's serious about about improving public education will stop using selective data analysis and have an honest discussion about it.

But, like I always say—this isn't about helping the kids.

Thomas Gaudio contributed to this story.