The LA Times reports that Greg Schiller, a popular high school science teacher, was suspended because two of his students made projects that "appeared dangerous to administrators."

One project used compressed air to propel a small object but it was not connected to a source of air pressure, so it could not have been fired. (In 2012, President Obama tried out a more powerful air-pressure device at a White House Science Fair that could launch a marshmallow 175 feet.)

Another project used the power from an AA battery to charge a tube surrounded by a coil. When the ninth-grader proposed it, Schiller told him to be more scientific, to construct and test different coils and to draw graphs and conduct additional analysis, said his parents, who also are Los Angeles teachers.

A school employee saw the air-pressure project and raised concerns about what looked to her like a weapon, according to the teachers union and supporters. Schiller, who said he never saw the completed projects except in photos, was summoned and sent home. Both projects were confiscated as "evidence," said Susan Ferguson, whose son did the coil project.