Block Schedule


A block schedule is a system for scheduling the middle- or high-school day, typically by replacing a more traditional schedule of six or seven 40–50 minute daily periods with longer class periods that meet fewer times each day and week. For example, a typical block-schedule class might last 90 or 120 minutes and meet every other day instead of daily.

School-by-school variations in block-scheduling systems are numerous, but the most common formulations include:

  • A “4 x 4” block schedule in which students take four 90-minute classes every day and finish a course in one semester rather a full school year.
  • An “A/B” or “alternating-day” block schedule in which students take eight 90-minute classes that meet every other day.
  • A “trimester” schedule in which students take two or three core courses at a time, with each class meeting daily, over three 60-day trimesters.
  • A “75-15-75-15” schedule in which students take four 75-minute classes every day and finish courses in a semester, with each semester followed by an intensive 15-day learning-enrichment course or remedial program. Another variation is the “75-75-30” schedule, which uses only a single 30-day intersession rather than two 15-day intersessions.
  • A “Copernican” schedule in which students have longer classes for core academic subjects during one half of the school day and shorter daily periods for electives such as physical education or music during the second half of the day.


The following are a few representative arguments that may be made by advocates of longer instructional periods and block scheduling:

  • Fewer class periods and interruptions during a school day reduce the amount of time that teachers spend on routine administrative or classroom-management tasks—such as taking attendance, handing out and collecting materials, or preparing for and wrapping up activities—which increases the total amount of time students are engaged in more meaningful and productive learning activities. Some studies have found that significant amounts of class time are commonly devoted to non-instructional tasks—in some cases, leaving only 15 or 20 minutes (out of 45 or 50) for instruction and learning. In a traditional eight-period school day, students also spend more time in the hallways and moving between classes, which further reduces the total amount of the school day that can be devoted to learning and may also increase disciplinary issues.
  • Teachers are able to utilize more varied or innovative instructional techniques when class periods are longer—they can cover more content with fewer interruptions, provide students with more attention and one-on-one support, and they can engage students in more sustained, in-depth learning activities, including more sophisticated projects, teamwork-based exercises, or other activities that could not be easily completed in 40 or 50 minutes. Also, the more students that teachers have to see each day, the less time and attention they can devote to each student. Consequently, student-teacher relationships may not be as strong, and students, particularly those with significant learning needs or disabilities, may not get the personal attention and support they may need to succeed in a course.
  • Scheduling fewer classes per day reduces burdens on both teachers and students. In a traditional eight-period day, for example, teachers need to prepare for up to eight courses and possibly double the number students. Consequently, teachers may be forced to rush the grading of work, provide less substantive feedback to students, or hastily plan and organize lessons. Students must also prepare for more courses, which can be overwhelming and have an adverse impact on learning. For example, homework assignments may need to be more superficial, since teachers have to take into consideration the time it will take students to complete homework for six or more classes on a given night, rather than four.

Critics of block schedules tend to claim that students (particularly at certain developmental stages) cannot stay focused for longer periods of time, that knowledge retention will be diminished if classes do not meet every day, or that students will fall behind more readily or quickly if they miss a day of school. The “4 x 4 block schedule” has been more heavily criticized since students may end up with a half-year or even yearlong gap between courses. For example, students might take French I during the first semester of their freshman year, but their French II course will not be scheduled until the second semester of their sophomore year, resulting in a twelve-month gap in language instruction. Critics may also question whether teachers actually teach differently when classes are longer or whether teachers have received enough professional development to modify their teaching strategies or lessons in ways that will make the most effective use of longer periods. In some cases, negative perceptions of block schedules stem not from the strategy itself, but from failed attempts to implement such a schedule in a school, or from educators who have had negative experience with a poorly organized or executed block-scheduling strategy. Since block scheduling often requires significant changes in way lessons are structured and taught, teachers may also resist or dislike the system because they feel less confident with the new format or they are emotionally attached to more familiar scheduling systems.

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