Union leaders lauded the efforts to reduce both the achievement gap and class size, but they say district employees felt let down. (Sarah L. Voisin/The Washington Post)

Montgomery County’s school board adopted a budget that is expected to lower classroom sizes next school year and accelerate efforts to narrow the achievement gap, part of a $2.46 billion plan that also cuts back on raises pledged to more than 22,000 school district employees.

The recently approved budget will boost spending by $139 million — 6 percent — in what school officials say is the largest funding increase since at least 2008.

The county’s biggest property tax hike in seven years — a rise of nearly 9 percent that will add $326 to the average residential bill — will help fund the school system’s budget increase, which comes after years of surging enrollment in the 156,000-student district.

In a system with a growing number of English-language learners and children from low-income families, the new funding will steer more resources to high-needs schools, beef up math and literacy efforts, and add more than 300 teachers to help reduce class sizes.

There also will be additional support for minority achievement programs, as well as an uptick in counselors and psychologists.

“This was a very special budget season, and I think it comes at a good time as we transition into a new superintendent and get back on track with some special areas that need addressing,” said Michael A. Durso, the school board’s president.

Jack R. Smith, formerly Maryland’s interim state superintendent of schools, is slated to take over the top job in Montgomery on July 1, following a long, sometimes fitful search for a schools chief following the 2015 resignation of Joshua P. Starr.

Starr lost the confidence of some board members, and he resigned amid reports that he did not have enough votes to win a new four-year contract.

The new budget his successor takes on was both praised for going nearly $90 million over the state minimum funding level and lamented for doing away with some pay increases that teachers, principals, cafeteria workers and bus drivers thought they were getting.

The Montgomery County Council had pressed for employee concessions, saying it could not justify a tax increase if there was not a greater show of sacrifice from the county and its school system. The board agreed to trim back raises in exchange for the added funding.

Raises were pared for both county and school district employees.

Under the new plan, school personnel will get a 1 percent cost-of-living raise on July 1, and those eligible will get step increases that average 3.5 percent.

Employees had previously been promised the step increase and a 2 percent cost-of-living bump that would have gone into effect Sept. 3, as well as an additional step increase due in March 2017 that would have made up for a raise postponed amid the recession.

In all, they will get roughly half of what was negotiated in their contracts — a result that drew a mixed reaction.

Union leaders lauded the new funding and district efforts to lower class sizes and narrow the achievement gap that separates white and Asian students from their black and Hispanic peers. But they said many employees also felt let down.

“It’s disappointing,” said Chris Lloyd, president of the county teachers union, noting that employees have twice relinquished recent negotiated raises. “I think there is some anger, but mostly frustration. This is not a one-time event. This has repeated itself over the last several years.”

He said some employees are questioning the nature of the contract negotiation process and whether county officials should be included earlier. He also noted that Montgomery’s starting teacher salaries lag behind several Washington-area jurisdictions, which he said could be an issue as the school district prepares to hire a large number of teachers.

“As we try to diversify our teaching workforce to better reflect our student population, we have to ensure that MCPS is a desirable place to work, and salary and benefits is a significant factor in that,” he said.

Other union leaders also voiced disappointment with the process. The board reopened negotiations, but no agreement was readily reached, so it relied on a provision of state law that allows it to trim negotiated raises without unions signing on.

“The opportunity for give and take, the opportunity for discussion and options, was not as open and not as authentic as it had been in the past,” said James Koutsos, president of the Montgomery County Association of Administrators and Principals.

Durso, the school board president, said he understands employee concerns but said “when you look at the big picture, I think what we did was right and necessary.” He called the salary increases that employees will get “pretty significant.”

Frances Frost, a past president of the countywide council of PTAs, said two of the organization’s priorities were reflected in the budget agreement: more focus on the achievement gap and class size reduction.

Not every class will be smaller, but the district’s guidelines will change, meaning schools could see smaller classes in some grades.

“I think parents are pleased,” she said. “There is grumbling about the taxes, but most are pleased about the money going toward education and areas they feel are important.”