The majority of Jefferson County Public Schools students start classes in two weeks. Superintendent Sheldon Berman announced several new initiatives for the school year today.One of those changes has more than half the district’s high schools switching to a trimester schedule. Berman says trimesters allow students to take five, 70-minute classes for three, 12-week periods."It reduces class size, so teachers can focus more effectively on the students they have, and it enhances their ability to give more challenging assignments because they’re grading fewer students," says Berman.He expects more high schools to switch to trimesters next school year. Another change to district high schools includes a new curriculum called "Facing History and Ourselves". It’s offered at 24 high schools and investigates the history of genocide in the world and citizens’ moral choices in those events.The 2008-09 school year will also feature the district’s first-ever single-gender schools. The former Southern Leadership Academy and Iroquois Middle School are now Frederick Law Olmsted Academies North and South. Boys will attend Olmsted North and girls will attend Olmsted South.The new school year also brings the opening of a new middle school, John L. Ramsey Middle School in southeastern Jefferson County.Berman says he’s confident the district’s remaining vacant principal positions will be filled before the first day of school. Classes start in two weeks, and there are still three unfilled principal positions.Berman says there’s still time to fill those spots, but the final choice isn’t up to him. It’s up to each school’s Site Based Decision Making Council."There may be an SBDM council that says ‘we looked at the candidates and we really would like an interim for the year’ and they could make that choice," says Berman. "It is late for some of the schools and they may want to open up that option and I know I’ve talked to at least one school about that possibility."The district will have 525 new teachers this year. JCPS has just over 99-thousand students enrolled for the upcoming school year.