A plan to improve the struggling Westminster Public Schools was narrowly approved Thursday by the State Board of Education.

The Democrat-controlled board voted along party lines to approve the plan, with the Democrats voting in favor and the Republicans voting against.

The 4-3 vote followed months of negotiations and appeals between the 10,000-student district and the state.

Westminster is the first metro-area district in Colorado to face state intervention after more than five years of low performance on state English and math tests. It is the only district in the state, and one of a few in the country, that has tried to roll out competency-based education district-wide. Instead of traditional grade levels, the district moves students through instruction when they prove they’ve learned a concept.

As part of the improvement plan, the district has hired consultant AdvancEd to help diagnose problems interfering with the rollout of its teaching model and other achievement problems at each of the district’s underperforming schools.

The district previously hired the company to review its school improvement efforts. AdvancEd granted the district a five-year accreditation under their standards. The group also accredits Valor Christian High School, schools in the Cherry Creek School District and schools under the Roman Catholic Archdiocese of Denver.

Under its plan, Westminster will also work with Denver-based Marzano Research to train and better prepare teachers to use the competency-based model. Marzano will open a new lab school in the district in the 2018-19 school year. Called Marzano Academy, it will be run based on the company’s research.

Last week members of the state board pushed back on Westminster’s plan, saying it lacked clarity and didn’t make clear the roles the two companies would play.

Even though the district added new details to its plan, some state board members still balked.

“Will this program work?” Republican Steve Durham asked. “I hope so. But I’m not sure it’s the kind of change that can ensure that.”

Earlier in the meeting Durham attempted to strip the district of its accreditation, a seal of approval from the state. But only one other board member, Republican Joyce Rankin, supported his motion.

State board members have increasingly voiced concern about how much authority external partners such as AdvancEd and Marzano should have in low-performing schools. A majority of plans have mirrored Westminster’s. Other options include closing schools or turning them over to charter operators.

Westminster Superintendent Pam Swanson told the board’s Republican members that she rejected their premise that the district hasn’t been proactive in improving.

“We’re really pleased the board upheld Westminster’s plan to move forward,” Swanson said after the meeting. “We believe we’re doing great work. We believe we’ve had a great trajectory.”