Updated

More than 600 teachers and classroom aides looking to get an early start to the Thanksgiving holiday weekend skipped school Tuesday in San Francisco, leaving officials desperate to find substitutes.

In the San Francisco Unified School District, 432 teachers – around 12 percent of its instructional workforce – called in sick or took a personal day, SFgate.com reports.

District data showed that a few were off for bereavement or training, but 179 special education and preschool aides also were not in schools Tuesday.

Officials at the district tried to find substitutes to fill all their roles, but fell short. The district required more than 100 central office staff members with teaching credentials to watch over students for the day, SFgate.com reports.

"It does create a sense of frustration when we have these kinds of numbers that happen for no apparent discernible reason other than it's a day before a holiday," Superintendent Richard Carranza said.

The president of the local teachers union, Dennis Kelly, said under the teachers’ labor contract, they can schedule personal days at will instead of calling in sick, and they do not have to ask for permission.

Districts in other California cities did not have the same problem Tuesday, SFgate.com reports.

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