SAN FRANCISCO (KPIX) — We’re taught at an early age that things are better when everyone plays by the rules, but sometimes that’s not exactly true. Case in point: Glen Park Elementary in San Francisco.

“My son was in tears every morning, getting dropped off, because it’s…who’s gonna be our teacher today?” explained Emily Sims, the parent of a Glen Park Elementary first grader.

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Back in October, the first grade teacher at the school went on medical leave. The district says union contract rules prevent permanently filling a vacancy if the teacher’s return status is uncertain.

Since then, the class has been a revolving door of substitutes. 13 different teachers have headed the class this year so far.

Parents say the disruption has had a jarring effect on their kids.

“They have stomach aches and they’re crying in the morning and they don’t want to come to school,” said parent Kendra O’Dwyer.

At one point there seemed to be a solution. Principal Jean Robertson’s daughter, who already worked in an after-school program, got her credential and happily took over the class.

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But about a month later, the district removed her from the position, citing its own rule prohibiting nepotism.

“We don’t believe that a family member is necessarily best suited to supervise another family member,” said SF Unified School District spokesperson Gentle Blythe. “So in this case, the principal is the supervisor of the classroom teachers.”

Parents like Emily Sims questioned the logic of adhering to the rule in a crisis situation.

“I understand that rule to not hire family members if there’s a line of teachers out the door waiting for the job,” said Sims. “But that’s just not the case in the SF district. They’re desperate for teachers.”

Sims is right. The teacher’s union points out 79 positions remain open in the district simply because they can’t find enough teachers who can afford to live in the Bay Area.

At Glen Park, the school’s reading specialist has been reassigned to take over first grade, but the parents say it would be better for everyone if the district would be willing to relax its nepotism rule in such desperate times.

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“I guess they’re going by the letter of the law but they’re not taking into consideration what’s really best for the kids, and that should be the bottom line,” said O’Dwyer.