CARY — Wake County students should expect to spend an extra 10 minutes a day in school next year instead of five additional days of classes.

State legislators are now letting school districts add five days or 25 hours of classes instead of requiring both. In a move expected to be matched by most of the state’s 115 school districts, Wake County will add the additional time instead of the extra days.

So, on Tuesday, the Wake school board approved 2013-14 school calendars having 180 days.

Administrators will come back to the board later with plans for how they’ll add about 10 minutes to each of those school days. Classes could start earlier or end later or some combination. Finding a solution that will work for most of Wake’s 150,000 students and their families won’t be easy.

“It’s something we’ll have to struggle through,” school board Chairman Kevin Hill said. “I’m sure that we, as a Wake County system, will come up with a solution.”

Most high schools start at 7:25 a.m., so starting classes earlier could draw complaints from people who say teenagers need more sleep.

Most elementary schools start at 9:15 a.m. and end at 3:45 p.m. Ending later could draw complaints from families who already don’t like how late their young students are arriving home.

Historically, state law has required North Carolina public schools to have 180 days of classes and 1,000 hours of instruction. Last year, the new Republican-led General Assembly changed the law to say that the school year should be both 185 days and 1,025 hours to increase learning time for students.

But many local school officials complained that the extra days would take away time for teacher training and increase the cost for running school buses. Wake school officials said it also would create logistical problems adding days to the multitrack year-round calendar used at some schools.

Wake, like most school districts, received waivers for the 2011-12 and 2012-13 school years from the State Board of Education.

In the meantime, state legislators amended the law to give districts the flexibility, beginning in 2013-2014, to add either the days or time. In return, school districts will not be granted waivers.

“Adding the time will have less of a financial impact on us,” Hill said.

Leanne Winner, a lobbyist for the N.C. School Boards Association, said it’s expected that most districts will add the hours and not the days.

Hui: 919-829-4534