Why February?

Here's a piece of city schools history: The midwinter break enjoyed this week by New York City public school students and teachers began as an energy-saving measure imposed during the oil crisis of the 1970s. It remains a part of the schedule because of a budget deal between the city and the teachers' union.

In 1977, New York City's Board of Education unanimously approved closing schools for a week in February during the 1977-78 school year. A memo from the board at that time called the decision "an experiment for the purpose of energy-saving." (The city was also in the midst of a fiscal crisis, so it didn't hurt that it would also be money-saving.)

The new calendar did not reduce the number of instructional days, but rearranged some days off so that schools could shut off lights and turn down thermostats for a whole week. A week off also meant a break from transporting students during a time of long lines at the gas pumps.

But saving energy is not today's reasoning for a February recess.

The midwinter break became a permanent feature of the New York City school calendar as part of a budget-cutting deal between the Board of Education and the teachers' union in 1991.

The United Federation of Teachers agreed to defer $40 million in wages for a few years. To make the deal more enticing to teachers, the board agreed to bundle existing days off so that teachers would have a weeklong break.

The vacation period made it onto the school calendar in 1992, prompting a mixed response from parents left to pick up the child care pieces ever since.