After years of discussion, the St. Paul school board wisely voted this week to have middle and high school students start their school day one hour later beginning in 2019. Yet some board members expressed reservations about the decision and said they would be open to revisiting it.

The board should stay the course, and here's why: For more than two decades, studies have shown that adolescents are not early-morning people. Research on sleep and academics has concluded that teens are more alert and ready to learn during mid- to late-morning and afternoon hours. A recent RAND Corporation study suggests that any increased costs such as bus transportation and scheduling are worth the investment, because benefits include higher academic performance and mental and physical health.

On Tuesday, board members voted 5-2 to start middle and high schools at 8:30 a.m., which should give older students a much-needed extra hour of sleep. The trade-off is that at least half of the district's elementary and K-8 schools will start an hour earlier at 7:30 a.m. Any school with a 9:30 a.m. start time will keep it.

Several board members remain torn about the change, citing surveys in which about 50 percent of district parents oppose it. One complaint comes from those who don't want their little ones waiting for buses before 7 a.m. Some families are also concerned about how jobs and after-school activities will be affected.

There are indeed some challenges to address, but families and schools have until 2019 to adjust. And in a district working to increase achievement, removing obstacles to student learning should be the priority.

Some other Minnesota school districts faced with similar complexities found ways to work through the challenges — even if it meant that some families were initially unhappy. Edina and Minneapolis moved their start times nearly 20 years ago. Still, unfortunately the majority of Minnesota districts have earlier start times for older students. According to data collected by the Minnesota Sleep Society, 87 percent of the students in grades 9-12 start before 8:30 a.m.

The St. Paul board voted in December 2016 to change start times beginning in 2018. By delaying the change until 2019, the board gave new Superintendent Joe Gothard time to incorporate the schedule into his strategic plan for the district. Unfortunately, it also gives the board more time to possibly reverse a decision that should have been made years ago.

Board member Jeanelle Foster, who voted for the change Tuesday, also told the St. Paul Pioneer Press, "We do have another opportunity to stop this." That shouldn't happen. We sympathize with those school board members and administrators whose e-mail and voice mail boxes no doubt include messages from parents who oppose the change for any number of reasons.

The message to parents should be consistent: We are here to educate your children, and research shows that later start times help teens do their best work in the classroom.

St. Paul school leaders should do what it takes to follow through on their latest vote.