DES MOINES — When the Highline School District decided to give its kindergarten students a full day of learning — a few years ahead of a state requirement — they had to get creative to find places for the 5-year-olds to learn their ABCs.

At Des Moines Elementary, a basement storage room that flooded each winter was repaired and repurposed as a kindergarten classroom. With voters rejecting two bond proposals to build schools and add classrooms, better facilities are likely years away.

Highline is one of 261 districts in Washington struggling to plan for new classroom space to meet upcoming state mandates for all-day kindergarten and 17-to-1 student-teacher ratios in grades K-3.

The mandates are set in the McCleary decision, a 2012 Washington Supreme Court order on school funding that said lawmakers were not fully paying for basic education and were relying too much on local tax-levy dollars. Since then, lawmakers have been seeking money to hire more teachers but have done little to supply the classrooms needed to house those classes.

A recent survey of Washington school districts by the Office of the Superintendent of Public Instruction found more than 5,500 additional classrooms will be needed to satisfy the McCleary requirements.

That adds up to an estimated $2 billion in new schools across 261 of the state’s 295 school districts, according to Gordon Beck, OSPI director of school facilities and organization.

Those numbers do not include last November’s voter-approved initiative calling for smaller classes in all grades.

The state’s largest school districts need the most new classrooms, but they aren’t the only ones scrambling to find room for students by the 2018 McCleary deadline. Even if the state finds the money to pay for more teachers, the system for building classrooms takes time.

Districts that cannot pass a school bond measure have no access to local dollars or state matching funds. A legislative attempt to make it easier to pass school bonds by requiring only a 50-percent majority instead of a super-majority rule failed this year.

Rep. Hans Dunshee, D-Snohomish, says the Legislature needs to find new ways to get schools built.

“We have a statewide responsibility. If we left that part to the locals, we would have kids in visqueen (plastic sheeting) tents,” he said.

He supports a simple majority requirement for school bond measures, noting some districts have never been able to pass a bond with a 60-percent majority.

In the past 10 years, nearly all the more than 200 failed bond measures across the state garnered more than 50 percent of the vote.

“The representatives here, who don’t want to pass the simple majority, all win their elections by a simple majority. If it’s good enough for a politician, it ought to be good enough for a school,” Dunshee said.

Dunshee would like to see a more scientific study of classroom needs, since he believes the OSPI survey data may be exaggerated.

He estimates the need is about halfway between the $700 million mentioned in the McCleary decision and the $2 billion estimate from the OSPI survey.

The House’s proposed capital budget for the next two years includes an extra $22 million to help local districts bypass the local dollar requirements to apply for state matching grants. More than $600 million was set aside for school construction in both the House and Senate capital budget proposals.

Full-day kindergarten used up the majority of the Highline School District’s existing capacity and portables were brought in, said Duggan Harman, the district’s chief of staff and finance.

“Portables are a solution of last resort, but a solution we had to go to more and more,” Harman said.

Highline has estimated it will need another 110 new classrooms by the 2018-19 school year to decreased class sizes to 17-to-1 in K-3. The McCleary decision is not the district’s only space problem. They also need room for the thousands of children who have moved into the district over the past five years.

“We don’t see any end in sight,” Harman said. The next step may be two shifts of students in some buildings.

The Spokane School District estimates it would need six more elementary schools to move toward a ratio of 17 kids per teacher in K-3. Similar to Highline, Spokane offers full-day kindergarten using existing space.

The district recently passed a bond, but it didn’t include money for new schools. District officials felt voters would reject a bigger tax request, said Mark Anderson, associate superintendent of school support services.

For now, the state’s second largest school district also will rely on portables.

Spokane planned to add portables to get to a 20-to-1 ratio in grades K-3, in hopes that the Legislature would pay for the other classrooms they need.

“It’s kind of a wait-and-see game for us,” Anderson said.