Boston City Councilors ordered up a hearing today at which to press Boston school officials to explain how the new BPS Zum (pronounced "zoom," but for obvious reasons not spelled that way) app that was supposed to make BPS buses run as softly as a cloud instead led to some buses not showing up in the morning for an hour or more - and some kids riding buses home for up to three hours as their poor, befuddled drivers tried to navigate Boston's dropped-bowl-of-spaghetti roads. Read more.