- Student: Class representing a student with all the information related to the course he's in currently identified by an id.
- Certificate: Class representing a sigarra's certificate identified by type.
- Request: Associative class representing the certificate request of a student identified by an id.
- Admission Data: Class representing the student's admission data to a course.
- Frequency Regime: Class representing a student's frequency regime of his/her current course.
- Status: Class representing the student's status of his/her current course.
- Exam: Class representing a UC's Exam.
- Improvement Enrollment: Associative class representing an improvement exam enrollment of a student.
- UC: Class representing a certain UC identified by code.
- UC Enrollment: Associative class representing a student's enrollment in a UC.