The Livermore school board this week unanimously approved moving its two comprehensive high schools from semester to trimester schedules beginning next fall.

As a result, students are expected to be taking more but shorter classes that meet every day.

The move, approved Tuesday night, will be made on a three-year trial basis, coinciding with the district's recommendation for the new schedule.

The district cited many positives to the change -- among them, a bigger variety of classes and more opportunity to take them. But many speakers, including students and teachers, listed to the board a wide range of concerns, from more homework to continuity in classes between the trimesters, to students not having enough time for multiple extracurricular activities. There were also worries there was not enough notification that such a change was in the works.

"There's no guarantee teacher X will pick up where teacher Y left off," said James Peters, a junior at Granada High.

But with little discussion among trustees, they approved the change 5-0.

"If we don't take this opportunity, we will not be doing students the service they need," board member Anne White said.

Livermore Education President Keith Pickering-Walters said the teachers union did not take a position on the trimester plan, as opinions are varied among its more than 700 teacher-members. Hours before the vote, the district and the union signed a memo that included funding, class size and preparation time concerns. However, the union is concerned about the financial effects of the board's decision, which comes as the union and district are at odds over pay negotiations covering this school year.

The district estimated $2.25 million cost for the trimester system over the three years, plus a one-time $130,000 for more textbooks. Three teachers at Livermore High and eight at Granada High would need to be hired. The district said no new facilities would be needed, though some teachers believe otherwise.

The new schedule divides the year into three 12-week trimesters with four 70-minute class periods and one 75-minute period offered each day. Students would take four to five classes and get a new schedule each trimester.

The first period of the day would start at 8 a.m., with the last ending at 3:05 p.m., though Granada High Principal Chris Van Schaack said that could be changed slightly. Wednesdays would have students out earlier for teacher collaboration.

Plans are to raise graduation requirements, now at 230 credits, to 270 because students will be earning more credits per year. Classes are five credits each.

Van Schaack and Livermore High Principal Darrel Avilla recommended new requirements be phased in to not take current students by surprise.

There also were many questions about whether this change is timed well, in light of upcoming state budget cuts. But Superintendent Brenda Miller said that even in a worst-case scenario the district can afford it. She also noted that an arbitrator's ruling in favor of the union over last year's Livermore High schedule and teacher work day length would cost the district an additional $300,000 per year to satisfy under the current schedule.

Pickering-Walters said the union should not be blamed, as it was the district which made the schedule.

The two schools now operate on separate schedules, each based on two 18-week semesters.

Eric Louie covers education. Reach him at elouie@bayareanewsgroup.com or 925-847-2123.