The number of students at CPS schools this year dropped by 13,804 compared with last year. View Full Caption DNAinfo/Alisa Hauser (File)

CHICAGO — Chicago Public Schools student enrollment dropped by 3.5 percent this year compared with last, according to information provided by the district.

That could mean layoffs for 300 teachers and support staff members.

During the last 10 years, enrollment has fallen 6.8 percent at public schools in Chicago, with half of that drop coming since September 2015, according to district enrollment data.

The drop in enrollment was "steeper than expected," district officials said in a statement Monday. In July, officials said they expected the district's enrollment to drop by just 5,240 students.

"Even with declining enrollment, we know that every dollar matters, and we will continue to work with our school principals to help protect classrooms and minimize the impact of having fewer students in schools,” said CEO Forrest Claypool.

CPS enrollment dropped from 392,285 during the 2015-16 school year to 378,481 this year for a total drop of 13,804 students, district officials said.

That means cuts at 306 schools throughout the city will total $30.7 million.

In all, Chicago schools have seen their budgets slashed by $170 million since September 2015, according to data released by the district.

However, schools where those cuts "would prevent them from offering critical academic programming" will get an additional $5.7 million, district officials said.

Because the district funds schools based on the number of students they have, 195 schools will gain $20 million, district officials said.

RELATED: Check Your School's Final Budget And Enrollment

Teachers and support staff who will be laid off because of the enrollment decline will be notified on the 20th day of school — Oct. 3, district officials said.

The enrollment figures released Monday were based on the number of students who attended class on the 10th day of school, Sept. 19.

The announcement of the drop in enrollment at CPS schools came on the same day Chicago Teachers Union officials announced that 95.6 percent of union members who voted last week opted to approve the first strike since 2012.

In August, CPS officials laid off nearly 1,000 teachers and members of the district's support staff.

The latest round of cuts — the fourth in 12 months — comes after schools across the city saw their budgets slashed by $140 million in August.

On Twitter, union officials said the cuts were "too familiar, and just one reason why more than 95 percent of our voting members chose to authorize strike."

Too familiar, and just one reason why more than 95 percent of our voting members chose to authorize strike #faircontractnow https://t.co/VcKck3eEeX — ChicagoTeachersUnion (@CTULocal1) September 26, 2016

Schools got about 7 percent less this year for each student in kindergarten through 12th grade compared with last year, officials said.

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