Evaluation of Grading Systems of Some Tertiary Institutions in Nigeria

Abstract

Since the advent of course system of education in tertiary institutions world-over, Cumulative Point Average (CGPA) has been in use as an Assessment Instrument instead of Cumulative Weighted Average Mark (CWAM).  Consequently, mapping of percentage marks into an n-grade points system which is required to generate the much needed CGPA has become necessary.  Countless methods of mapping have been witnessed across different tertiary institutions.  In addition, the number of grade point, ‘n’ varies from institutions to institutions.  While it is a universal fact that ‘n’ can take any value less than 100, it is nevertheless important to know that the value of ‘n’ has never been greater than 12.  In Nigerian tertiary institutions, the value of ‘n’ varies between 4 and 7 while 5 is the most common.  However, simply equating ‘n’ to 100 is not sufficient to convert the percentile system to an n-grade points system in order to generate the required CGPA.  It is discovered that there is no sound mathematical method employed to relate the CGPA ranges normally used to classify degree to the percentage scores earned by individual students.  This paper (paper 2) is primarily written to establish the required parameters and the most suitable format of an n-grade points system which is referred to as a Non-Graded Fail Grading System with a fail grade, ‘F’ assigned a zero value (NGF/GS_F=0) while another paper (paper 3) presents the development of the required mathematical relationship between CGPA and percentage scores ranges.