There are basically three possible things that can happen to a student at a school:
The student remains in the same class as the this year
In this case you do not need to do anything in Untis.
The student leaves school
In this case you should highlight the student and click on button <Delete lesson/student>. The student will be deleted from the master data.
The student transfers from one class to the next
Select previous year's class and the current class and click on button <Transfer lesson/student>.
The figure above illustrates the following situation:
All students of class 13 have left school except for student Aladdin. He will continue in class 13.
All students of class 12 will transfer to class 13 except for Aberlour and Ardbeg. Aberlour will repeat year 12 and Ardbeg will leave school.