Block scheduling

Block scheduling is a type of academic scheduling in which each student has fewer classes per day for a longer period of time. This is intended to result in more time for teaching due to less time wasted due to class switching and preparation.

Conversion to block scheduling became a widespread trend in United States schools in the 1990s. Prior to that, many schools scheduled classes such that a student saw every one of his teachers each day. Classes were approximately 50 minutes long, but under block scheduling, they became approximately 90 minutes long.

One way of doing block scheduling is shown in the example table. Instead of taking 6 classes every day, students take 3 classes every other day, spending twice as long in each class. The example reverts to a six-period day on Fridays. Another way of distributing the classes would be to have "A" and "B" days on alternate Fridays, or to alternate "ABABA" weeks with "BABAB" weeks.

Most American high schools use a six or seven-period day, and classes run for one semester (half a year). A method called 4x4 block scheduling splits the academic year into quarters, and uses a four-period day. This leaves eight slots available for classes during a semester (four classes in each of two quarters). The 4x4 method is somewhat more flexible in that students can take two sequential classes (such as Algebra 1 and 2) in the same semester (in different quarterts), which would not be possible on a traditional schedule. This also allows students in their final year to fail a third-quarter class but repeat it in the fourth quarter in order to graduate.

Part of the motivation for block scheduling is to prepare students for taking end-of-grade/end-of-course standardized tests used to measure student achievement (and in some school districts, teacher pay and school funding). Another is social--to foster cooperation among students. This is done by having students work in groups (called "cooperative learning") to help them learn from each other, rather than have classes that focus on teacher-delivered content, as some experts believe that students learn better from peers than from professionals.

Effectiveness
A study by the College Board found that students taking AP courses on a 4 x 4 block schedule score less well than do students taking the same AP course on a traditional full-year schedule.

Some schools have compensated for this by making AP courses last for the entire school year, providing essentially double the instruction time of normal classes, but this results in a dramatic reduction in the number of courses a student can take. Some schools that make AP courses year long offset this by having students always choose a pair of AP courses during class registration. The student will go to the first AP class one day, and the other AP course the next day. Therefore, the student takes the same number of courses as other students, but both AP classes last for the duration of the year.

Criticism
Block scheduling has been criticized as resulting in class periods that exceed the attention span of students, resulting in less retention and watering down of the material to maintain interest. It may result in gaps of weeks or months where students are receiving no instruction in a specific subject like math or history, and critics say this results in retention problems and the need for more remedial review.

Students who miss a block-scheduled day will miss a considerable amount of material in a single subject, possibly making it more difficult to catch up. Mid-term transfers between schools with different schedules is problematic due to the need to repeat certain material while other material has been missed.