Some Chicago students started the school year Tuesday without a classroom teacher, a perennial problem. But Chicago Public Schools said the number of vacancies was down compared to the previous two years, with some 700 unfilled teaching positions — a 3.3% vacancy rate.

Students in special education classes were more likely to encounter vacancies. The district said Tuesday it needed 294 more special education teachers, a vacancy rate of 7%. 

Both rates are down from last school year —  when the district reported a 4% overall teacher vacancy rate, and 8.5% in special education, a higher percentage of overall open positions than Houston, New York City or Los Angeles. (The district has also added both regular teacher and special education positions this school year.) 

Chicago’s first-day vacancy rate shows that the district continues to struggle to find people to do a job that has been recognized as both difficult and undervalued

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Statewide, district superintendents have described an acute need for teachers, prompting both the state legislature and the Illinois school board to act. Illinois eliminated a basic skills test, raised the teacher minimum wage, and now allows retired Chicago teachers to act as substitutes. Advocates have called the efforts a good start, but they are skeptical that they will turn the tide significantly. 

Teacher working conditions have also been at the heart of contract negotiations between the Chicago teachers union and the district. 

The district has tried to recruit new teachers by offering million-dollar student teacher development contracts, teacher residency programs that pull from the ranks of assistants and community members, and mentoring programs in particularly hard-to-staff schools. 

The lack of teachers affects tens of thousands of Chicago students. Schools rely on substitutes or pull in support staff to run classrooms. The schools most likely to have long-term vacancies have a majority black student body, according to an investigation by WBEZ. 

As in the rest of the country, the two hardest school jobs to fill in Chicago are in special education and bilingual instruction. Both require specialized skills, and also ask a lot of teachers both practically and emotionally. 

The Chicago Teachers Union has addressed the shortage by calling for hundreds of new jobs to support teachers, particularly special education aides and mental health professionals, and by arguing for more flexible prep time and increased pay for teachers.

“Teaching in CPS is not for the faint of heart,” union President Jesse Sharkey said. “That’s why we want to win real improvements in this contract.”

In response, Mayor Lori Lightfoot has promised teachers a 16% raise over five years, but has not responded to the demand to add more support staff in the teachers contract. 

Researchers, and teachers themselves, say the best answer for finding and keeping teachers is a combination of short-term policies — like forgiving student loan debt or lifting residency requirements like those in Chicago that require most teachers to live within city limits — and long-term reforms, such as improving pay and working conditions to make teaching a more attractive job.

As the school year goes on, the vacancy numbers likely will shift. In recent years, the district reported that, as it hired more teachers and the school year progressed, vacancy rates declined. Last year, the district said vacancy rates fell from 4 percent on the first day of school to 3 percent by mid-November. 

Until then, schools continue looking: On Tuesday, the first day of school, the district posted dozens of job listings on its CPS “careers” site, including a second-grade teacher for English language learners at Sidney Sawyer school on the Southwest Side and a middle school English teacher at Mozart School, in Logan Square. 

Related: Teachers question district timeline for hiring support staff