Occasionally, student performance on an assessment is lower than expected. Instructors can choose to modify the student scores on the assessment to equalize the scores.
A simple method for curving grades is to add a certain number of points to each student’s score. A common method for determining how many points to add to a final test score is to find the difference between the highest grade in the class and the highest possible score. For example:
- If the highest percentage grade in the class was 88%, the difference is 12%. You can add 12 percentage points to each student’s test score.
- If the test is worth 50 points and the highest score is 48 points, the difference is 2 points. You can add 2 points to each student’s test score.
Methods for curving a test grade in Blackboard Learn include:
- Method 1: Download the test’s Grade Center column, apply the desired curving calculations in a spreadsheet program, and upload the resulting grades into a new Grade Center column.
- Method 2: Manually override each student’s original test grade.
Method 1: Download Grades, Adjust Test Scores, and Upload to Grade Center
This method requires no manually typed grades and is preferable for large classes. These steps use Microsoft® Excel® to modify the downloaded grades file. The simple formula adds points to the original test grade. You can use more complex formulas if needed.
After uploading the adjusted grades, change the column settings for the original test grade so that it is no longer included in any calculated grade totals, and the new adjusted test grade column is used instead. Instructions for this task are included in the following steps. You can also remove the original test grade from students' My Grades pages.
Before you begin, make note of the first few values from the total column. After you upload a new Grade Center column, you can check to be sure it is being correctly included in calculations.
- In Full Grade Center view, point to Work Offline on the action bar and click Download.
- On the Download Grades page, in the Data section, choose Selected Column. Select the name of the column from the drop-down list.
- In the Options section, set the Delimiter Type to Tab.
- In the Save Location section, click My Computer.
- Click Submit.
- Click Download. In the pop-up window, click Save File and click OK. Note the file name and location.
If the file automatically saves to your Downloads folder, you can move it to a different folder and rename it to make it easier to locate.
Adjust Test Scores
- Locate the XLS file that you downloaded and open it in Excel.
- Click the first cell in the column immediately to the right of the test grade column. Type a column name. Use a name that will easily identify this column when you upload it to your course’s Grade Center. Choose a name that is not already used in the Grade Center.
- Select the cell below the new column's title and type a formula that will add a certain number of points to the original test grade.
Type this formula, replacing the number 7.5 with the number of points you decided on: =D2+7.5
- Press the Enter key. The cell updates to show the original test grade with the additional points added to it.
- Point to the cell’s bottom right corner. The fill handle appears (+).
- Drag the fill handle to the last cell in the column that you want to copy the formula to. Release the mouse to copy the formula to the selected cells and update their contents with new point totals. The formula automatically recognizes that the cell contents are part of a series and adjusts the formula for all cells in the column.
- In Excel, click Save. A pop-up message appears that warns you that saving the file as TXT may remove some features. Click Continue to save your changes to the file.
Upload Adjusted Scores to Grade Center
- Return to your course’s Grade Center. Point to Work Offline on the action bar and click Upload.
- Click Browse My Computer and select the XLS file you saved in Excel.
- Set the Delimiter Type to Auto.
- Click Submit.
- On the Upload Grades Confirmation page, notice that the original column has no data updates and your new column is listed for uploading. Click Submit.
- Scroll to the far right side of the Grade Center grid to view the newly uploaded column. By default, the new column is shown to students in My Grades and included in Grade Center calculations, such as the total column.
- By default, the new column's Points Possible is set to zero. Access the column’s header contextual menu and click Edit Column Information. Type a new value for Points Possible and click Submit.
The Points Possible value must be equal to the points possible from the original test. If you are using percentages, the points possible must equal 100.
- Change the settings for the original test column so that it is NOT included in the total column's calculations and NOT viewable by students. Access original test column's contextual menu and click Edit Column Information.
- On the Edit Column page in the Options section, click No for Include this Column in Grade Center Calculations -AND- click No for Show this Column to Students. Click OK in the pop-up window that verifies that you want to exclude the column from calculations.
Check the first few values in the total column to verify its calculations. The difference between the original values that you noted before beginning the process and the new values should be an increase by the number of points you added to each test score.
To learn more, see Grade Center Columns and Upload or Download Grade Center Items for Working Offline.
Method 2: Manually Override All Test Grades Individually
If you have a small number of test grades to adjust, you can override test scores one at a time in the Grade Center in two ways:
- Use the Manual Override tab on the Grade Details page. This is the recommended way to assign an override grade. After assigning the grade, you can add feedback for the user and notes for yourself explaining the grade change.
- Type directly in a Grade Center cell to assign an override grade for a test attempt.
To learn more, see Override Grades.