Waiting in line for the bus, a Pennsylvania kindergartener tells her pals she's going to shoot them with a Hello Kitty toy that makes soap bubbles. In Maryland, a 6-year-old boy pretends his fingers are a gun during a playground game of cops and robbers. In Massachusetts, a 5-year-old boy attending an after-school program makes a gun out of Legos and points it at other students while "simulating the sound of gunfire," as one school official put it.

Kids with active imaginations? Or potential threats to school safety?

Some school officials are taking the latter view, suspending or threatening to suspend small children over behavior their parents consider perfectly normal and age-appropriate — even now, with schools in a state of heightened sensitivity following the mass shooting at Sandy Hook Elementary in December.