Published: Jul 12, 2013 10:41 AM EDT

TALLAHASSEE, Fla. (AP) - Florida Education Commissioner Tony Bennett wants to make last-minute changes to the formula used to calculate annual school grades.
    
Each year the state hands out A-to-F grades that are used to reward top schools and sanction those that get failing marks.
    
But Bennett on Friday recommended a new rule that would limit a school grade from dropping more than one letter at a time. The state Board of Education will consider the change at a special meeting scheduled for next week.
    
The commissioner is responding to worries from school superintendents that recent changes to the grading system would create a large drop in the grades that are widely used by parents to evaluate schools.
    
The grades are based primarily on student performance on a series of high-stakes tests.

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