Our high school has a block schedule, none of the classes are "extras" - the kids have the same total # of classes they would have if they went to all classes every day. Lunch is not considered a "period" here - the entire high school eats lunch at the same time ever day. No classes are offered during that time, but there are a ton of clubs that meet over lunch. We have a few "early bird" classes, insanely early considering how early first hour starts anyway! They aren't in any core academics, but in elective subjects, and only happen when an extremely motivated teacher wants to teach them
polarbear
