DES MOINES, Iowa (AP) — A K-12 education spending plan moving through the Iowa Legislature will not keep up with rising annual costs for school districts, warned some superintendents who say they'll have to make cuts to balance their budgets.

Lawmakers in the Republican-controlled chambers appeared to agree on $32 million in new K-12 public school funding for the budget year beginning in July. That's a 1 percent increase to Iowa's $3.2 billion K-12 budget, the largest expenditure in a roughly $7.2 billion state budget. Per-pupil spending would go up by $67, totaling $6,731, according to the data.

Still, some details need to be sorted out. On a 29-21 vote, the Senate on Wednesday night approved an additional $14 million for various transportation expenses and to close some inequity in cost-per-pupil spending across school districts. The $46 million measure must bounce back to the House before it can reach Gov. Kim Reynolds' desk. It's unclear if House Republicans support the extra money.

Across the state, superintendents said they were planning to make cuts to balance their budgets.

In Marshalltown, the school district will see a reduction of up to $300,000 because of mandatory increases in utilities, wages and other expenses, said Superintendent Theron Schutte. The district will consider cuts to its administrative budget to avoid reductions to teacher staffing and curriculum offerings.

Schutte said the small increase is still better than the district had expected.

"We're certainly not celebrating that," he said. "It's still going to lead to us having to take a more serious look at positions."

The Fairfield Community School District in southeastern Iowa faces a shortfall of about $100,000 next academic year in part because of declining enrollment, said Superintendent Laurie Noll. She added the district has cut nearly $2 million from its budget over the last few years, including closing one of its three elementary schools.

"We are very lean already, and to have no new money, it will impact us again," she said. "We'll have to see where we can cut."

Republicans maintain funding for Iowa's roughly 330 school districts is adequate given the state's budget constraints. They note K-12 education hasn't experienced budget cuts despite mid-year reductions to other areas of state government in recent years.

Rep. Cecil Dolecheck, a Republican from Mount Ayr, spoke in support of the $32 million budget plan before a 57-40 vote Wednesday morning in the House. He said GOP lawmakers are working on other education-related proposals that will give districts more spending flexibility, including a $10 million fund for transportation costs in rural areas.

"When we consider the entire education package the majority is putting forward, most if not all of my school districts are pleased and maybe even somewhat surprised that we're able to commit 1 percent new money," he said.

Reynolds has indicated she will support the funding pitched by her party, though it's less than the $54 million she'd proposed.

Rep. Walt Rogers, a Cedar Falls Republican who chairs the House education committee, challenged longstanding warnings from superintendents that more money is needed to avoid larger class sizes. He said the latest student-teacher ratio in Iowa is acceptable, and he defended the funding.

"I'm proud of the numbers that we have put forth and what we're doing for education," he said.

Dan Maeder, superintendent of Davis County Community School District in Bloomfield, said his district's elementary school has up to 28 students in some classrooms.

"If we want to lead the nation in education, we need to fund it like we mean it," he said.

Superintendents also said they're dealing with financial obligations that include increased spending for employee retirement plans. Contribution rates for employers and employees in the state's main retirement system, known as IPERS, will increase on July 1.

In northwestern Iowa, Estherville Lincoln Central Community School District Superintendent Tara Paul said she expects to receive roughly $92,000 in additional money for the next school year under the $32 million GOP plan. The new cost toward IPERS is a little over $53,000, leaving about $38,000 for staffing, textbooks, transportation, insurance and other costs. Those costs increase an average of 3 percent each year, Paul said.

"This is not for the frills or the extras, but to keep the buildings open and the district running year to year," she said in an email.

Des Moines Public Schools, the state's largest school district, expects to cut more than $11 million from its budget.

"Given our size the dollar amounts we're looking at are large, but every school district in Iowa is going to be facing these same decisions to one degree or another," said district spokesman Phil Roeder.