Class is made up of students who follow a common course of study. Pupils/students are grouped together in a class based on the highest number of common courses, usually compulsory studies. A class is the pedagogical structure in which each student is registered. Regardless of the level of study, a student is registered in only one class. Students from different grades may be present in the same class, as occurs in one-teacher or two-teacher schools. Conversely, a school may have a number of classes for the same grade.