Sometimes a quiz is harder than intended, or external factors affect class performance. The curve grading feature lets you adjust scores for students after the fact without editing the quiz itself. Curved scores are stored separately from original scores, so curves can be previewed, applied, and undone at any time.

Accessing Curve Grading

To curve grades for a quiz:

1. Navigate to PressPrimer Quiz > Reports.
2. Click the Curve Grading report card.
3. Select a quiz from the dropdown.

Only a quiz’s author or an administrator can preview, apply, or undo a curve. Other teachers can view curve results for quizzes their groups have attempted, but cannot change them.

Curve Grading is also available on the Reports screen of the front-end Teacher Dashboard, including applying and undoing curves, when the Educator add-on is on version 3.1 or higher. The same permission rules apply on both surfaces.

Curve Methods

Four curve methods are available, each suited to different situations:

Percentage Boost

Adds a flat percentage to all scores. For example, a 10% boost changes a 65% to 75% and an 80% to 90%. Scores are capped at 100%. This is the simplest method and gives every student the same boost.

Best for: When the quiz was uniformly harder than expected and you want a straightforward adjustment.

Square Root Curve

Applies the formula: new score = √(original) × 10. This gives the biggest boost to low scores and a smaller boost to high scores. For example, a 49% becomes 70%, a 64% becomes 80%, and an 81% becomes 90%.

Best for: When you want to help struggling students more than top performers.

Linear Scale

Multiplies all scores by the same factor so the current highest score reaches the target maximum. For example, if the top score is 85% and target is 100%, all scores are multiplied by 100/85. A 68% becomes 80%, a 51% becomes 60%.

Best for: When one student clearly earned the top score and you want to scale everyone relative to that benchmark.

Target Median

Calculates the current median score, then shifts every score up or down by the same amount so the median lands on your target. For example, if the current median is 58% and you set the target to 70%, every score goes up by 12 points. Scores are capped at 0% and 100%.

Best for: Standardizing class performance to a target level, common in higher education.

Previewing a Curve

Before applying a curve, you can preview the impact:

1. Select a curve method.
2. Configure any parameters (such as boost percentage or target median).
3. View the before/after chart showing the score distribution.
4. Review the impact table showing each student’s original score, curved score, and change amount.

The preview calculates results without saving anything, so you can experiment with different methods and parameters.

Applying a Curve

When you’re satisfied with the preview:

1. Click Apply Curve.
2. Confirm the action in the dialog.

The curved scores are saved to each affected attempt. The curve method and parameters are also stored so you can see what was applied.

Where Curved Scores Appear

Curved scores are visible in specific contexts:

• Curve Grading report: Shows both original and curved scores
• Student’s assignment list: Shows the curved score with a note explaining the adjustment

Original scores continue to be used in other reports, on quiz result pages, and elsewhere. This ensures historical data and psychometric analysis remain based on actual performance.

Undoing a Curve

Curve grading is non-destructive. To undo a curve:

1. Open the Curve Grading report for the quiz.
2. Click Remove Curve.
3. Confirm the action.

All curved scores are removed, and students see their original scores again.