First school officials say how important it is to be in class.
Then they tell them not to come.
More than 30,000 out-of-school suspensions were issued to public school students -- some of them repeatedly to the same students -- in kindergarten through 12th grade in Allegheny County alone in 2011-12, the most recent year for which countywide data are available.
The numbers illustrate the tension between keeping kids in class and keeping schools safe and orderly. In some schools, more than a third of students have been suspended at least once.
"If you're suspending a third of the kids, that's a huge loss in educational minutes," said Rob Horner, professor of special education at the University of Oregon and co-director of a federal technical assistance center on positive behavioral interventions and supports.