TEACHER - STUDENT LOAD. 4.10.1 Teacher class size for students in grades 6 – 12 will be limited to 140 students or less for a five-period day (except with regard to §4.10.2 §4.10.4 and science). If a teacher is assigned a sixth class, the roster must be 168 or less. [This provision settles HTA Grievance #2013-14- 7.]