They are perhaps the three sweetest words to a young person’s ear: School is canceled. And this week, students in New York City were able to savor the cheerful news further in advance than usual.  The decision to close schools is not easy for public officials, who often make the announcement just hours before the school day is scheduled to begin, perhaps in the very early morning or late the night before. But in the face of what could be a record-breaking snowstorm, Mayor Bill de Blasio said on Sunday afternoon that school would most likely be canceled Tuesday. It was made official at a news conference during lunchtime on Monday.  “Parents clearly got the message: Get ready for school to be off Tuesday,” Mr. de Blasio said at the Office of Emergency Management headquarters in Brooklyn. “Now we are formalizing it and saying school will be closed tomorrow, and this is giving them enough lead time to make the kind of arrangements they need.”  Students got the message, too, and eager anticipation spread across the city. Administrators on Monday morning did their best to keep little and not-so-little feet on the ground.  What was open and closed after a winter storm hit the New York region as of Jan. 27, 2015 at about 5 p.m.  As snow pirouetted through the early afternoon air, streams of bundled teenagers bustled away from Brooklyn Technical High School, grinning because they already knew they would not have to come back the following day.  Anthony Cuomo, 16, a junior (no relation to New York’s governor, who will not have the day off on Tuesday), said he would “probably” study for tests; at Brooklyn Tech, the storm falls during midterms. But studying was not foremost on his mind.  “I just don’t want to go to school in the storm,” he said.  Ava DiPietro, 14, said that despite the predictions about the power of the approaching storm, she doubted it would be strong enough to do what she most wanted: make her tests vanish.  In addition to scattered midterms, tens of thousands of students across the state are scheduled to take Regents exams this week.  The State Education Department announced that Regents tests scheduled for Tuesday, including algebra and global history, could be rescheduled for later in the week. A department spokesman said this was the first time such rescheduling would be permitted. Usually, students must wait until the test is next given, which in this case would be June. Students must pass certain Regents exams before they can earn a high school diploma.  The snow day on Tuesday will be the second under Mr. de Blasio; the first came last year on just his third day in office. But the city’s decision to keep schools open during a nasty snowstorm in February drew widespread rebuke from parents, other elected officials and even Al Roker, which was made worse when Carmen Fariña, the schools chancellor, declared it was actually “a beautiful day.”  And so students were not the only ones happy on Monday about the advance notice.  Deno Charalambous, principal of Aviation High School in Long Island City, Queens, said that years ago, he would sometimes arrive at school in winter at his usual time of 6 a.m., only to learn that he had a lonesome day in store.  “I was at school, and I would hear, ‘Schools are closed today!’ ” Mr. Charalambous said. This did not happen just once, he added.  Anthony Armstrong, principal of Nathaniel Hawthorne Middle School in Bayside, Queens, said that for his school, the storm came at a fairly calm time.  “Our midterms are over, thank God, so this was a normal week,” Mr. Armstrong said. “Anything that had to be rescheduled could be without much interference. Just make sure that Wednesday there is school, please.”  A version of this article appears in print on January 27, 2015, on page A22 of the New York edition with the headline: With Early Notice of Closed Schools, Students (and Adults) Cheer. Order Reprints| Today's Paper|Subscribe
Mayor Bill de Blasio announced that city schools would be closed on Tuesday because of the snowstorm, giving some students a reprieve from pending exams.