The bells at some Minneapolis public schools could ring at slightly different times next year.

District officials are seeking opinions on altering start and dismissal times to get a better picture of the effects and complexity behind a school-day schedule.

An online survey gauging students' and parents' satisfaction with current daytime schedules and how they could improve will gather opinions until the end of the month and has generated some criticism of possible rescheduling — though no plans are on the table.

The district is surveying opinions now in case of any major changes in the future, said Stan Alleyne, a district spokesman. This way, parents' and students' thoughts will be logged and accessible as district leadership continues the discussion, he said.

"We think it's a good time to look at what we're doing," Alleyne said. "We haven't made any decisions."

Officials are mulling a pilot program that would affect a handful of Minneapolis schools' start times next year, though it is unknown which schools and to what extent. The district will announce any changes in February and will then create the plan with stakeholders.

"The few pilot schools may start earlier, they may start later or we may not make any changes at all," Robert Doty, chief operations officer, wrote in an e-mail to Minneapolis public schools staff Friday.

The St. Paul public schools board considered implementing later start times for its high schools last year, drawing from University of Minnesota research showing later schedules positively affect students' academic performance and health as well as community feedback.

Though the board voted the proposal down in October, the discussion is ongoing.

The district will consider later start times for the 2016-17 year after studying a pilot program at Johnson High School, which will move the day's start time to 8:30 this fall. It is also testing a new partnership with Metro Transit.

Shifting Minneapolis schools' daytime schedules would be a multilayered process, Alleyne said, which would require changes to bus schedules and after-school activities.

Not to mention the impact on thousands of homes.

"For some families a 7:30 [a.m.] start time would be great; for other families, it wouldn't work at all," said Ryan Vernosh, a St. Paul schools administrator who led discussions on the potential changes in his district.

Seven Minneapolis high schools and some middle and elementary schools moved school start times from 7:15 a.m. to 8:40 a.m. almost a decade ago.

Those students don't experience a natural, biological shift into sleep until later than 11 p.m. on average, no matter a school day's start, according to the University of Minnesota study.

So although widespread scheduling changes require work, lead researcher Kyla Wahlstrom said it's important that factors — like students' biological clocks — are equally considered so they aren't sleep-deprived and can perform to their fullest academically.

"At some point, you have to make sure that schedules don't drive the health and well-being of students," she said.

Jessica Lee is a University of Minnesota student reporter on assignment for Star Tribune.