PORTLAND, Ore. – Oregon education officials are reviewing “block” class schedules in Portland Public Schools after parents complained students are not receiving enough instructional time.

“Portland’s schedule is built on 90-minute blocks: four periods one day, four different class periods the next. Students are seldom in class all of that time, and since the schedule started three years ago, parents have complained about the long stretches of free time,” Oregon Public Broadcasting reports.

State regulations require at least 130 hours of instruction time, and parents filed a complaint with the state recently arguing Portland’s block schedule falls short of the requirement.

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District officials haven’t officially responded to the complaint, but district spokesman Robb Cowie told the news network the district acknowledges “that currently, classes at most of our high schools are not meeting the 130 hours, as defined in the state rules.”

Teachers contend the lack of instructional time is causing student burnout, because students are required to learn the same amount of material in less time, Oregon Public Broadcasting reports.

“They manage – they can take care of themselves, academically,” math teacher Chuck Slusher said of his best students. “But it comes at a price, for sure. I really see them stressed out and exhausted.”

Slusher and social studies teacher Fred Fox said it’s the students who are already struggling that suffer the most from the compressed schedule.

“The lower-performing students are the students who struggle the most,” Fox told Oregon Public Broadcasting, “and if they get behind, they don’t have the skills and the experience to get caught back up.”

District officials contend they started to take action to address the situation before parents complained to the state, by adding teachers to the high schools, as one example. But parents think they could and should do more.

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“We felt the pace of acceleration just really had to increase, and that’s why we went to the state,” parent Tracy Barton told the news network.

The concerns in Portland exposed similar shortages of instructional time in other Oregon school districts, as well. School officials in the Tigard-Tualatin, Beaverton, and other districts also use block schedules that do not meet the state requirement, Oregon Public Broadcasting reports.

Portland school officials are negotiating adding days to the school year with the local teachers union to compensate for shortage in instructional time, but that change would obviously require the approval of the union, which would probably demand a lot more money for teachers.

Regardless, Fox suggested any days added to the school calendar to be tagged onto the beginning of the year, which would give students extra time to prepare for state assessments in May.