"学校作息时间表" can be translated into English as "School Timetable" or "School Schedule".
"School Timetable" is more commonly used to refer to a detailed plan of classes, activities, and breaks throughout the school day.
"School Schedule" can also be used, though it might have a slightly broader connotation, encompassing not just the daily routine but also other scheduled events like exams, meetings, or extracurricular activities.
In most contexts, especially when referring to the daily routine of classes and breaks, "School Timetable" would be the most appropriate choice.