Grade schemes are a way of organizing users' performances on grade items into levels of achievement. Each achievement level has its own range of acceptable percentages and a symbol. A perfect example of this is a letter grade scheme. You can set up a scheme that will display a letter grade based on the percentage of the total points earned by a student. The system uses a percentages scheme by default.
In the following scheme a student who recieves an 88% will see a B+ for their grade.