Fix Gradescope Bubble Sheet Auto-Split Errors

Gradescope may display an "Unable to confidently auto-split" error when it cannot identify the boundaries between scanned bubble sheet submissions. Instructors can review, reorder, split, merge, or remove affected pages before manually creating submissions.

Quick Links: | Problem | Environment | Solution | Root Cause 

Problem

Gradescope may be unable to automatically separate an uploaded bubble sheet PDF into individual student submissions. When this happens, a yellow error message appears indicating that Gradescope cannot confidently identify the submission boundaries. Some pages may require manual review, reordering, or removal before submissions can be created. This prevents instructors from completing the normal automatic submission creation process until the affected scans are corrected.

Environment 

This article applies to you if all of the following are true:

• You are using an instructor-uploaded bubble sheet assignment in Gradescope.
• You have uploaded a PDF containing scanned bubble sheets through Manage Scans.
• Gradescope displays the message "Ready to Create Submissions (Unable to confidently auto-split)" above an uploaded file.

Solution

To fix bubble sheet scans that Gradescope cannot automatically split into submissions, follow these steps:

1. Open the affected assignment's Manage Scans page.
2. Locate the PDF displaying the yellow "Ready to Create Submissions (Unable to confidently auto-split)" message.
3. Select Show to expand the uploaded PDF and display its pages.
4. Scroll through the pages until you find the scans displaying yellow error messages.
5. Move your pointer over the affected page thumbnails to reveal the magnifying glass icon.
6. Select the Magnifying Glass icon to inspect the page and identify possible issues, such as an unexpected extra page.
7. Reorder, split, or merge the affected pages as needed to correctly organize the student submissions.
8. If an unnecessary page is present, select the red X in the upper-left corner of its thumbnail to remove it from the upload.
9. Review the remaining pages to verify that they are arranged correctly.
10. Select Create Submissions to finish processing the corrected scans.

Gradescope will now create individual submissions using the manually corrected page arrangement. You can review the resulting submissions before proceeding with grading.

Root Cause

When Gradescope processes a scanned bubble sheet PDF, it uses the expected bubble sheet template to identify and separate individual submissions. If Gradescope cannot confidently determine where one submission ends and another begins, it does not automatically split the entire PDF. Unexpected extra pages, incorrect page arrangements, or scans that cannot be reliably matched to the template may require manual correction before Gradescope can create submissions.