The number of Florida high schools that earned an A or B grade dropped by 12 percentage points in 2014, according to the state's preliminary A–F grades released Thursday, but officials noted Florida's high-school graduation rate was at an 11-year high.

Grades released Thursday by the Florida Department of Education showed that the number of A-graded schools dropped from 49 percent last year to 36 percent this year.

The number of schools given a B did edge up slightly from 33 percent to 35 percent.

Of Florida's 520 high schools, just over 71 percent were graded A or B this year, compared to 83 percent in 2013.

The Florida Department of Education noted the grading scale was adjusted upward. Because more than 75 percent of schools last year earned a grade of B or above, the number of points needed to earn a certain grade increased this year.

Education Commissioner Pam Stewart said the statewide graduation rate of 76.1 percent was 0.5 percent increase over 2013 and nearly 17 percentage points higher than a decade ago.

"I am confident that our state's educators will continue providing a high quality education that builds on the progress we have made," said Stewart. "As always, there is room for improvement. We will continue working closely with all of our school districts to provide the support necessary to ensure Florida students have access to the best education."

Bay area grades

In Hillsborough County, three-quarters of the public high schools earned A or B grades during the 2013-2014 school year, despite the fact the state raised the bar, making it more difficult to earn such grades.

Ten of the district’s 27 traditional high schools earned A grades, 10 earned B grades, and 7 earned C grades. No high schools were assigned D or F grades. Most of the schools showed a higher level of performance. If the state had not raised the cut scores, 19 high schools would have earned an A grade.        

The Hillsborough County high schools with the highest overall point totals are Plant, Newsome, and Steinbrenner high schools.

"It’s important to note that the state continues to raise the bar and our students and teachers continue to meet the challenge," said Hillsborough School Superintendent MaryEllen Elia. "The hard work being done in our high schools is reflected in a higher level of achievement."

Pinellas County had five high schools earn As.

Osceola, Tarpon Springs, Palm Harbor University, East Lake and St. Petersburg Collegiate high schools all earned the top grade. No Pinellas high schools earned a D or F, although six earned C grades. And four of the six, Dixie Hollins, Gibbs, Largo and Northeast received a C grade after being B schools last year.

In Pasco County, almost 70 percent of public high schools earned an A or B grade, and none received a D or F for the 2013-2014 school year. Mitchell, Wiregrass Ranch, Sunlake and River Ridge highs schools all erned A grades.

"I’m ecstatic about the significant increase in our graduation rate," said Pasco Superintendent Kurt Browning. "I can also say that I’m pleased that most of our schools either maintained or raised their grades, especially when the bar was set higher this year, but I’d still caution anyone from reading too much into these grades."

Manatee County high schools earned four A’s, two B’s and two C’s.

Braden River High, Lakewood Ranch High, Manatee School for the Arts and State College of Florida all scored high enough to earn A grades. Manatee High and Southeast High both received B grades while Bayshore High and Palmetto High received C grades.

This marks the third-straight year every Manatee District high school scored a C or higher.

"Last year over 80 percent of all high schools in the state of Florida received an A or B rating, therefore a law went into effect to raise the bar," said Manatee District Deputy Superintendent for Instruction Dr. Diana Greene. "Last year, every Manatee District high school earned an A or B grade from the state, which was the first time we had accomplished that feat as a district. With the new criteria in place this year, it takes more points to earn an A or B."

Polk County saw 10 of 16 high schools keep the same grade. McKeel Academy of Technology was the lone Polk high school to earn an A.

Four Hernando schools earned B's with Central improving from a C.

In Citrus County, Crystal River (C) and Lecanto (B) high schools dropped a letter grade while The Academy of Environmental Sciences earned the county's lone A.