ROCKLAND, Maine — On Wednesday evening, the Regional School Unit 13 board called for combining the two middle schools in Rockland and Thomaston in addition to abandoning its experiment of a divided high school.

The board voted 9-3 to merge Rockland District Middle School and the Thomaston Grammar School and have all sixth-, seventh- and eighth-graders go to one school no later than September 2015. The members were divided, however, on where the consolidated middle school should be located.

There was also division on whether the sixth-, seventh- and eighth-graders from St. George School ultimately should be required to attend the consolidated middle school. St. George is developing a plan to withdraw from the six-community district and has a kindergarten-through-seventh-grade school.

Superintendent Lewis Collins said the district could combine the Rockland and Thomaston middle schools at Rockland District Middle School. Board member William Pearce of Rockland agreed the consolidated middle school should be located in Rockland because it is the newer school, as it was designed to be a middle school and includes a library.

Other board members, however, suggested the current Oceanside High School West in Thomaston as the site for the combined middle school.

Board Chairwoman Esther “Tess” Kilgour said St. George should be left alone and its middle school students be assigned to that town’s school. St. George began its withdrawal efforts after the school board voted to assign its eighth-grade students to Oceanside High School West in Thomaston.

Board member Loren Andrews of Cushing said that St. George had created a tremendous school, and the board should not disrupt that.

Board member Donald Robishaw Jr. said that if St. George is part of the district, its middle school students should attend a single district middle school.

Board member Sally Carleton of Owls Head said the board should review educational data to determine whether the St. George School is more successful and whether it should be merged with a single middle school.

The 9-3 board vote saw Andrews, Pearce and George Emery of St. George opposed to the middle school merger. St. George would not be affected by the merger vote taken Wednesday.

Andrews voiced concern about where the fifth-grade students from Rockland and Cushing would go with such a merger. Fifth-graders in those two towns currently go to the middle schools.

The board also overwhelmingly voiced support for returning to one high school serving ninth- through 12th-graders at Oceanside High School East in Rockland. Eighth- and ninth-graders attend Oceanside West in Thomaston and 10th- through 12th-graders go to Oceanside East in Rockland. That two-school system has been in place for two years.

Robishaw said the eighth- and ninth-grade students feel they are not part of a middle school nor part of the high school.

While supporting a single high school, there was considerable disagreement on whether it could be accomplished by the start of the 2014-15 school year.

The superintendent presented a summary of a report from Cordjia Capital Projects Group of Camden and Portland which stated that additions to the high school to accommodate more students would cost $5 million to $7.2 million. The work would include a 3,000- to 4,000-square-foot cafeteria and a 12,500- to 14,000-square-foot addition to Oceanside East for the estimated 150 freshmen. Additional parking would also be needed, according to the report.

Robishaw said that both the merged middle school and sending ninth-graders back to a single high school should be done at the same time to reduce disruptions.

In another matter discussed, the board was also sharply divided on whether the Gilford Butler School in South Thomaston and the Owls Head Central School should be closed. The board voted 9-2 to consider closing the Gilford Butler School, but the chairwoman stressed that it was a nonbinding vote to give the administration direction. Emery and Pearce voted against the measure, and Andrews abstained.

The board voted 5-7 on considering closing Owls Head with Sherman Hoyt of St. George, Robishaw, Carol Bachofner of Rockland, Christine Curtis of South Thomaston and Arvilla Collins of Thomaston supporting the measure

“No, never, no way, no how,” said Andrews. “These small elementary schools are the heart and soul of the communities. They are ideal for young students. Let’s not mess with success.”

Andrews said there is no plan on where those students would go. Gilford Butler has kindergarten through second-grade students and Owls Head has third- through fifth-grade students.

Board member Carol Bachofner of Owls Head supported closing both elementary schools.

“We can’t afford 11 buildings for fewer than 2,000 students,” Bachofner said.

Board member Sherman Hoyt said if the two towns were not willing to pay for the cost of keeping them open, he would support their closure.

Kilgour said she would support closing Gilford Butler and building an addition to Owls Head so that it would serve kindergarten through fifth-graders in Owls Head and South Thomaston.

Pearce said before he would support the closure of those schools and move them to South School, the district needs to improve the academic performance and reputation of the South School. Ultimately, he said, a new school for elementary students in Rockland, Owls Head and South Thomaston should be built.

Robishaw said school closures of the past and proposed are all from the east side of the district, the former School Administrative District 5, and none on the west side, the former SAD 50. He also said the Lura Libby School should be considered for closure at some point.

State law requires that the school board vote by a two-thirds majority to begin the school closure process. There are then referendums held in each town where a school would be closed. If they vote to keep the schools open, they would have to pay the extra costs of operating the school.

During the public comment session of the Wednesday meeting, Gerald Weinand of Rockland voiced concern about the board considering such actions without having performed the planning required under its recently approved strategic plan.

Weinand said he served on a committee for the Rockland-area school district seven years ago, and one of its recommendations was to close the MacDougal School in Rockland and the Gilford Butler School in South Thomaston. MacDougal since has been closed and demolished and the students assigned to the South School in Rockland.

The committee’s recommendation, however, was contingent on the district building an addition to South School to handle the MacDougal students and an addition to the Owls Head Central School to accommodate the influx of Gilford Butler students. Neither addition was built, he pointed out to the board.

Rockland resident Jesse Butler said that small schools such as Gilford Butler and Owls Head are important to those communities.