Mount Holyoke College assigned students letters from A to E before anyone studied whether it worked.
In 1897, Mount Holyoke College in Massachusetts adopted a grading system that assigned students letters based on their academic performance.1 The original scale used five letters: A for scores of 95 to 100, B for 85 to 94, C for 76 to 84, D for 75 (the minimum passing mark), and E for failure. The letter F, which later replaced E at many institutions, was not part of the original scheme.
Before letter grades, American colleges used a variety of systems. Yale introduced a four-point scale in 1785. Harvard experimented with numerical rankings, grouping students into divisions, and a 100-point percentage scale at various points in the nineteenth century.2 William and Mary used descriptive categories like "orderly, correct, and attentive." No system was standard.
The letter grade spread rapidly through American secondary schools and universities in the early twentieth century, driven by the growing need for a simple, portable measure of student performance that could be understood across institutions.3
Grade point averages, calculated by converting letters to numbers on a four-point scale, became a standard metric for college admissions, scholarship eligibility, and employer screening. By the mid-twentieth century, a student's GPA functioned as a portable credential, summarizing years of academic work in a single number.3
The system has been criticized since its inception. Research on grading reliability has consistently shown that different evaluators assign different grades to the same work, and that the correlation between grades and later professional performance is weak.4 Several institutions, including Brown University and Reed College, have adopted alternative systems. Brown allows students to take courses on a satisfactory/no-credit basis, and does not calculate GPA.3