Under the new rules, if a school does not have at least a quarter of its students meeting high reading standards, its grade will drop by one letter.

Orange County Schools chief Ronald Blocker heads the state's assocation of district school superintendents.

He worries about how low performing schools will be impacted by the new grading system.

“If you lived in those school communities, one would ask the question, what happened? Did something go wrong? And they don’t realize it’s a recalibration. The students aren’t performing any less. The teachers aren’t teaching any less.”

Blocker added schools which have been A graded in the past could also find themselves dropping down a grade.

"They've gotten used to that, almost drunk on the success of being high performing schools. There are some that have been A schools ever since the state started grading schools. Then all of a sudden they're no longer an A school. Their community will be concerned, realtors will be concerned," he said.

Blocker said the Board of Education revised its original plan- and removed an automatic F grade for schools not meeting reading standards.

But he said he’s still concerned the new system will be a challenge to implement.