Grade Curve Calculator
Flat Curve (Add Points)
Add a flat number of points to every score, or curve to set highest score to 100
Square Root Curve
Apply a square root curve (lower scores benefit more)
Bell Curve (Normal Distribution)
Apply a bell curve based on class mean and standard deviation
Formula
Flat: Curved = Score + (100 - Highest) | Sqrt: Curved = sqrt(Score) x 10 | Bell: Curved = Target Mean + Z-score x 10
Frequently Asked Questions
What is grading on a curve?
Curving adjusts scores to account for exam difficulty. Common methods include adding points to all scores, using a square root curve, or fitting scores to a bell curve (normal distribution). The goal is to ensure grades fairly represent student ability relative to the exam.
How does the square root curve work?
The square root curve takes the square root of your percentage and multiplies by 10. This benefits lower scores more: a 49% becomes 70%, while a 81% becomes 90%. The formula is: Curved Score = sqrt(Original) x 10.
Is curving fair to students who did well?
Curving helps lower scores more than higher scores, which can feel unfair to top students. However, most curving methods still maintain the relative ranking of students. A student who scored highest before the curve will still score highest after.
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