Intense blocks of learning with more frequent breaks
More breaks throughout the school year allow students to rest and recuperate before the next school session begins.  This resting period helps students retain information but is not as long as a 10 to 12 week break. Students still retain the information when they return to school.  More frequent breaks also help students stay more motivated and focused for the spurts of class instruction. Frequent breaks help students stay on track and feel less dread about the starting of the traditional school year.  Year round school gives teachers the opportunity to create new material and take more breaks. This would prevent burnout and increase teacher engagement and passion for their subject and job. Year round schooling promotes engagement and participation for both teachers and students.
Frequent breaks from year round schooling can prevent students from getting settled into a routine. Just as students would become comfortable with their teachers, subject matter, and environment, students would still have a three-week break and have to start from scratch.  Having to constantly start over after frequent three-week breaks can cause stress, anxiety, and emotional distress in students.