Grading in education is the application of standardized measurements to evaluate different levels of student achievement in a course. Grades can be expressed as letters (usually A to F), as a range (for example, 1 to 6), percentages, or as numbers out of a possible total (often out of 100). The exact system that is used varies worldwide.

In some countries, grades are averaged to create a grade point average (GPA). GPA is calculated by using the number of grade points a student earns in a given period of time. A GPA is often calculated for high school, undergraduate, and graduate students. A cumulative grade point average (CGPA) is the average of all the GPAs a student has achieved during their time at the institution. Students are sometimes required to maintain a certain GPA in order to be admitted to a certain academic program or to remain in that program. Grades are also used in decisions to provide a student with financial aid or a scholarship.

Grades are seen as an indicator for academic success and ability, and GPA is thought to indicate future job effectiveness and success. In addition, research has shown a correlation between GPA and future job satisfaction. Studies have also shown that a higher GPA leads to a higher income.

Students were given assessments as far back as 500 B.C. but no methods existed to formally measure student performance or track mastery of the subject. In the mid 1600s, Harvard University started to require exit exams to evaluate students, but they were not scored with letter grades.

The first record of a grading scale for students was at Yale University. Yale University historian George Wilson Pierson writes: "According to tradition the first grades issued at Yale (and possibly the first in the country) were given out in the year 1785, when President Ezra Stiles, after examining 58 Seniors, recorded in his diary that there were 'Twenty Optimi, sixteen second Optimi, twelve Inferiores (Boni), ten Pejores.'" By 1837, Yale had converted these adjectives into numbers on a 4-point scale, and some historians say this is the origin of the standard modern American GPA scale.

Bob Marlin argues that the concept of grading students' work quantitatively was developed by a tutor named William Farish and first implemented by the University of Cambridge in 1792. That assertion has been questioned by Christopher Stray, who finds the evidence for Farish as the inventor of the numerical mark to be unpersuasive. Stray's article also explains the complex relationship between the mode of examination (oral or written) and the varying philosophies of education these modes imply to both the teacher and the student.

The A-D/F system was first adopted by Mount Holyoke College in 1897. However, this system did not become widespread until the 1940s, and was still only used by 67% of primary and secondary schools in the United States in 1971.

Working to earn higher grades can cause students to prioritize short-term learning over life-long learning. These kinds of grades are only short-term snapshots of how much a student has learned in a given period of time and only partially reflect the actual performance. They do not take sufficient account of the individual development of students. Students often do not learn for their future life or out of interest in the material, but only for the grades and the associated status, which promotes bulimic learning.