Hey!

In CBSE Boards, a student gets roll number from school in all the classes except for 10th and 12th in which board exams are conducted. If you are in 11th class, then you would have been provided with a class roll number which is most probably a two digit number. Whereas, when a student is enrolled in class 10 and 12, CBSE board exam roll numbers are provided to the student. Only your board exam roll numbers have many digits.