You often read articles about charter schools whose students do wonderfully on standardized tests even though admission is by random lottery. The implication is that all we have to do to Fix the Public Schools is to do in all the other schools in America whatever it is that works so wonderfully at this one school with its (presumably) representative student body.

Of course, the parents who choose to apply their children to charter schools tend to be a notch above the average in the first place.

But there's another question I've never seen asked: Who says the admissions lottery is completely random?

The charter schools say their admissions are totally random.

But why would you believe them?

A few years ago, I applied my son to a new charter high school founded by the best teachers from his public middle school. Admission was by random lottery. I dropped by the office and nervously asked a teacher, who had been at my kid's junior high school the year before, if my son's application had been chosen.

He picked up the list, "What's the name again?"

"Sailer."

The teacher looked at me. "The kid who got a 5 on the AP Biology test in 7th grade?"

"Uh, yeah. That's him."

He put down the list without looking further. "He got in."

"Well, could you check to make sure he's on the list of those who were picked in the lottery?"

The teacher gave me a look that said, "How can a smart kid like that have such an idiot for a father?" and repeated. "He's in.

I looked blank.

He patiently reiterated, "Don't worry about it. He's in."

"Oh," I said. And then I smiled.

He smiled back, happy that he didn't have to spell it out any further.