How can one generate a "C" standard normal distribution
of grades? First, one can take the raw scores from an exam and
calculate the mean, median, mode, standard deviation, and coefficient
of variation. The quick check for a normal distribution is to
see whether the mean, median, and mode are approximately equal
to each other. If this is the case, one then can move up and
down the mean by one standard deviation to generate the C+, C,
and C- raw score grades and assign their numerical equivalents
on a 4-point scale. At the second standard deviation level one
has the "B" and "D" range, and at the third
standard deviation, one has the "A" and "F"
range. A downloadable spreadsheet
module provides a numerical illustration, complete with an
automatic examination histogram generator.