Just as they did at this time last year, school superintendents throughout the region are counting days and checking calendars to calculate the new - and ever-changing - last day of school.

The number of school closings this winter varies slightly throughout the region, but the recent storms will mean students will be in school longer in June. And some seniors will have to wait a few more days to wear their caps and gowns.

New London public schools have had six snow days through Monday, pushing the last day of school at this point to Monday, June 15 - a planned full day - for students, and June 16 for staff, district spokeswoman Julianne Hanckel said. The district hasn't touched any scheduled vacations during the school year, and with the last half of June still open, that seems unlikely.

"We have a 15-day window," Hanckel said.

Last week, new Superintendent Manuel Rivera started his tenure in New London by declaring a snow day, saying at the time that he would consider using Saturdays to make up some snow days, calling it "a great idea."

State law prohibits school districts from extending the school year into July, as that is the new fiscal year and July school days would not count for 2014-15, Norwich Superintendent Abby Dolliver said.

Schools may have caught a break this year, because Labor Day was early, Sept. 1, meaning school systems began the school year earlier.

So far in the region, Preston schools and Lyme-Old Lyme schools have the latest ending date, June 18. Both districts have had four snow days and originally had scheduled June 12 as the last day of school. Preston requires 184 student days, while Lyme-Old Lyme has 183 student days.

Some high schools in the region set their graduation dates for the last day of school, making it a moving target. New London and Waterford have not set graduation dates yet, and Stonington's school calendar states that graduation will be the last day of school.

"We do not set our graduation date until after April 1," Montville Superintendent Brian Levesque said. "Typically, it is the last day of school."

Waterford follows the same strategy, Superintendent Jerry Belair said, setting the graduation date in April, usually for the last school day. As of Monday, Waterford had four cancellations, bringing the last day to June 17, Belair said.

The Ledyard school district began the year with the last day of school scheduled for June 11, but the district intends to add the four accumulated snow days - so far - onto the June calendar, said Cathy Laro Patterson, Ledyard's superintendent of schools. Graduation is scheduled for June 20.

Norwich Free Academy, the largest high school in the region, which serves Norwich and seven surrounding towns, sets its graduation date early with the school calendar. The school is very reluctant to change graduation date - although it was forced to do so twice in recent years because of storm days - because the ceremony includes the class reunion of the class of 50 years earlier. Many of those alumni have to set travel plans early to attend the event.

NFA Head of School David Klein said NFA has had four canceled snow days, bringing the last day of school to Friday, June 12, which is graduation day.

Norwich public schools have lost four days to snow, and also have had several early releases and delayed openings, which count as school days. Norwich students attend classes for 182 days, and staff attend 186 days, putting the last day of school in Norwich at June 17 so far.

Dolliver and other superintendents said they don't plan to eat up February or April vacation days for snow days. Norwich only has Tuesday, Feb. 17, to add to a long Presidents' Day holiday weekend, and for April vacation, many families and staff have scheduled vacation trips.

"I don't like to touch that," Dolliver said.

East Lyme Superintendent James Lombardo agreed that converting school year vacations into snow makeup days is problematic. Some students would end up missing school if parents have planned trips.

Lombardo said as of Monday, East Lyme had canceled four school days, which would move the last day of school to Wednesday, June 17 - assuming there are no other snow days this year.

Graduation is typically held on the last day of school, but the Board of Education will officially set the graduation date at its meeting in April.

Lombardo said the district doesn't build a set number of snow days into the calendar, because the school board would likely end up having to change the calendar anyway to accommodate the actual number of snow days that occurred.

And snow days don't only affect school calendars - they also bring extra juggling for parents.

Armi Rowe of Waterford, a parent of two children, explained that a snow day can bring extra tasks for parents, on top of work: two to three hours of shoveling the driveway, walking the dog in the snow, and making sure children remain productive and don't waste their day by vegetating in front of a screen.

"For the kids it's fun, but for the parents it's really managing work," said Rowe.

Rowe, the owner of Rockumemories, a small business in Niantic, said if the roads are unsafe, she often will stay home and be in touch with customers. Snow can prevent customers from traveling themselves.

Ideally, on a snow day, her high school and middle school-aged children will get in some extra reading, not overdo electronics and spend some time in the snow playing with other children, or working on any school projects that need to be done, she said.

She said she sees some parents that happily sled with their children on snow days, but other parents "are pulling their hair out," because their children have "cabin fever" or find the unstructured time of snow days challenging.

If the school year stretches later in June, it could affect Rowe's planning for activities with her children's cousins, who are out of school earlier.

"The summer seems to get shorter and shorter each year," she said.

Waterford resident Jody Smith, who works part-time as a receptionist and has two daughters, ages 9 and 11, said the snowstorms have meant missing workdays, rearranging her schedule and rescheduling doctors' appointments.

Snowstorms this winter on Mondays have meant missing one of her scheduled work days. Delayed school openings also mean she can typically only work a half-day. Smith said fortunately her boss is very understanding, so she is able to make up her hours at other times.

While playing in the powdery snow of the late January blizzard was fun for her daughters, icy conditions mean they often have to stay indoors. Smith said her family prefers the warm weather, and she can't wait to see green grass, rather then snow.

"I'm ready for summer," she said.

Regina Mosley, a parent liaison for New London Parent Advocates, said she has heard many parents are frustrated with school cancellations, mainly out of concern for students' learning retention.

While "summer drop-off" is a common term for a loss in learning over summer vacation, some parents are concerned about a "winter drop-off," Mosley explained. After being out of school for an extended time, students may need to spend time reviewing material they learned earlier this winter.

Ultimately, though, Mosley said parents want students to be safe, even if it means extending school later in June.

"The safety of our children is most important," she said.

c.bessette@theday.com

Twitter: @Bessettetheday

k.drelich@theday.com

Twitter: @KimberlyDrelich