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The IRN number is assigned by ODE and is always six digits. This is followed by a dash (-) then the course number. The course number can be anywhere from 6-10 digits in length, depending on the course. All courses start with a 6 digit ‘base’ number. For year-long courses that are semesterized, we add a .1 or .2 to indicate the semester it should be taught in. In addition, some courses may have one or more letter suffixes on the end to indicate ESL, Block, Summer School, Gifted, etc. For a detailed explanation of course numbering, refer to the Course Numbering Standards. After the course number is another dash (-) and then the section number.
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