I found Florida’s Guide to Public High School Graduation For Students Entering Ninth Grade in 2010–2011. It doesn't mention it but it is one year out of date. It does highlight how many choices and types of high school programs and diplomas there are. Three year or four year, normal diploma or IB. And I don't think it even talked about the different special needs ones.
I also found this interesting report on Florida Virtual Education but I can't find the part about normal high school students being required to take a course to graduate. There is lots on FLVS move to be a school district (is this again?) and the sanctioning of virtual FL charter schools. I'll read it more closely later today.
BTW, what an impressive but mysterious site this is: Liberating Learning. No about us, no contact info, no way to even see what cover and what they don't? Virtual? Charter? Homeschool? Magnets? Private? Who are these people?