The Lawrence school district today released details of its proposed budget for the upcoming school year, calling for $148.8 million in total spending, an 18 percent increase over this past year.

Much of the increase is the result of the recent $92.5 million bond issue that district voters approved in April, which will fund major building improvements over the next few years in the district’s elementary and high schools.

But even without those projects, spending on day-to-day operations — what the budget documents refer to as “current expenditures” — would grow by $11.8 million, or 11 percent, to $120.7 million.

The Lawrence school board will hold a public hearing on the proposed budget next Monday at 7 p.m. The board is expected to vote shortly after the hearing to approve a final budget, which cannot spend more than what is outlined in the proposal.

The board voted July 22 to publish a notice of the public hearing, which outlined the total amounts that the district expects to spend out of various funds next year, and the estimated property tax mill levy needed to raise that money.

The documents released today, which are available on the district’s website, represent the first detailed explanations officials have to provided about how the district plans to spend the money. The 13-page “Budget at a Glance” document shows how spending is broken down by different categories, with comparisons to previous years.

Shannon Kimball, vice president of the board, said that while board members are just now seeing the detailed documents, they have been actively engaged in crafting the budget during public meetings for many months.

“We have been making decisions about spending all along, so I don’t feel like it’s a big surprise,” Kimball said. “We’ve been making decisions about what will be in it all throughout the previous year.”

Unlike cities and counties, school districts have relatively little discretion in deciding their overall spending levels. Those are determined by formulas set out in state laws, most of which are driven by student enrollment, poverty rates and the relative wealth of the district.

Among the decisions most affecting the budget, Kimball noted, was the agreement to ratify a new contract with the Lawrence Education Association. The contract provides an average 3 percent increase in salary and benefits for certified personnel, plus comparable increases for administrators and classified staff.

Those increases account for about $2.8 million of the total spending increase.

Other highlights of the proposed budget include:

• Instructional costs, the category commonly referred to as “classroom spending,” would increase by $8 million, or nearly 12 percent, to $75.5 million. That would represent 63 percent of total operational spending, not including capital outlay and bond-funded expenditures.

• Administrative expenses, including both central office and school building administration, would grow about 2 percent, to $6.6 million. That would represent about 5 percent of total expenditures.

• Per-pupil spending would grow about 10 percent, to $10,142.

• The estimated property tax levy would be slightly lower than last year’s tax rate: 57.921 mills, a decrease of 0.084 mills. That twould mean $1,332 in property tax for the owner of a home valued at $200,000, a difference of less than $2 from this year’s tax rate.

• The average salary, including benefits, paid to a full-time teacher in the district would grow to $55,230. The average administrator salary would increase to $96,192.