The class (or classification) is a column on the Student Term Summary by Division table (stud_term_sum_div.class_cde) that indicates the student's level at your institution. It is updated by the Classification Update process and is visible on the Student Inquiry window, Summaries tab, Division subtab, Classification column.
Your school can opt to have the process update two other tables, too:
Student Master
Student Division Master
Student classifications are generally based on the number of career credit hours the student has earned. The code may be one or two characters in length with a description of as many as 30 characters in length (example).
You may change or add new classification codes at any time. This column on the Classification table is updated when you run the student classification update process.