School districts inMichigan communities such Farmington Hills, Warren and Plymouth have been dealing with written threats that disrupt school days and cause police to expend time and resources searching for those responsible and ensuring student safety in class. The threats cost time and money. District officials say they lose hours of instruction time as schools are evacuated and searched; police say they spend thousands of dollars for bomb sweeps, backpack searches and detective work. Every threat must be investigated, district administrators and police officials say. They can't take the risk that the bomb threat found scrawled on a restroom wall is bogus. To read The Detroit Free Press article, click here.