Nine Pinellas County schools rose from a B to an A and a total of 18 saw improvement when the state recalculated accountability grades, according to a notice issued late Friday night.
While Pinellas and Hernando kept their districtwide C grades, Pasco and Hillsborough changed from C to B.
Statewide, 8 percent of school grades increased.
State officials said the changes reflect preliminary revisions to the initial grades released earlier this month in a year of tougher standards surrounding the state's testing system.
Bracing for lower grades due to the series of rapid changes, state and district officials had warned parents against making year-to-year comparisons.
The revisions involved 213 of the initially graded 2,586 schools.
The grade revision was good for Pinellas County's Fairmount Park Elementary School, which went from an F to a D.
Five Pinellas schools came off the D list: New Heights, Sandy Lane, Mount Vernon and Lakewood elementary schools, and Meadowlawn Middle School, which now are listed with C's.
Moving from a C to a B are James B. Sanderlin, Tarpon Springs and San Jose elementary schools.
Rising from B to A were Azalea, Bardmoor, Garrison-Jones, Northwest, Pinellas Central and Marjorie Kinnan Rawlings elementary schools; Fitzgerald and Seminole middle schools; and Plato Academy South K-8 Charter School.
In a statement, state officials described the revisions as part of a customary process to ensure accuracy and transparency.
"School grades are important to students, parents, teachers, principals, administrators and the community," Commissioner of Education Gerard Robinson said.
"And, while I am pleased that the continuous review process has resulted in better grades, we will continue to look for ways to improve the grade calculation process."
The grades become final in September.
The past several months have been fraught with criticism of the grading system, fueling a movement to de-emphasize high stakes tests.
In the statement, however, Robinson praised those schools and districts with higher adjusted grades, and the process that brought the changes about.
"The fact that 8 percent of school grades will increase not only affirms the hard work of Florida's students, teachers and district leadership, it demonstrates the value of the continuous review process," he said.
"The strength of our accountability system depends on the partnership between school districts and the department, and these revisions are a direct result of that process."
Marlene Sokol can be reached at (813) 226-3356 or firstname.lastname@example.org.