With three public high schools, all open to any student in the city, Portland has been able to offer families choices that no other Maine community can match.

But for the people scheduling school transportation, there hasn’t been much flexibility at all.

Now the school department is looking into a way to reduce the transportation problem while enhancing academic offerings: a rare public policy double win. The Board of Education should not let this opportunity pass.

The idea is to stop using yellow school buses to transport high school students, giving them bus passes for Greater Portland Metro instead. Students from all over town could reach Portland, Deering or Casco Bay high schools, and travel between the schools to take part in activities. The cost of the passes would be shared by the district and Metro.

That would not only save the district money, but it also would open up opportunities for interschool collaboration that would otherwise not be available.

Many school decisions are “driven” by transportation. For instance, the high school start times are set not according to what researchers say is the optimal time to get teenagers’ attention, but at a time early enough for the same buses to be used for a second trip to pick up younger students.

And the distance between the three schools makes it necessary for some programs to be duplicated unnecessarily – or more often in these times of tight budgets, not being duplicated, leaving some kids out.

A Metro pass gives students the flexibility to reach different locations at different times. It also gives the school board the flexibility to set schedules school by school.

Adding hundreds of daily riders to the transit system would be a plus for the whole city. More demand will lead to more service, which will lead to more use of the system. If the bus runs often enough, more people may chose to leave their cars at home, reducing traffic congestion and competition for parking.

The generation of children in high school now and their older brothers and sisters have already shown themselves to be less interested in driving than any generation before them. The millennials – the biggest generation in U.S. history – drive less than their parents and want better public transit. It would be wise for Portland to take advantage of that demographic trend.

Would this system be perfect for every student? Of course not. The current expensive, inflexible system doesn’t work for many students either. No other city in Maine has as much choice as Portland can offer families. Making Metro the high school transportation network would make those choices even more attractive.