Canvas FAQ and error messages in Flat for Education
Last updated October 29, 2026
Flat for Education works with Canvas through LTI 1.3 or LTI 1.1 (Legacy). This page answers the questions teachers and admins ask most about using it in Canvas, from student accounts and missing classes to assignments, grading and error messages.
General
How do my students get their Flat for Education accounts?
There's nothing extra to do. With Canvas, accounts are created when students open Flat for Education from Canvas, for example from a Canvas assignment. Just post your content in Canvas and their accounts will follow.
Why isn't my Canvas class showing up in Flat for Education?
The first time, the sync usually needs to be started from Canvas. Open Flat for Education from within your Canvas course, rather than signing in separately: this starts the sync and brings the class in.
Do the same whenever you add a new Canvas course and don't see it right away. Opening it once through Canvas is usually all it takes.
Assignments
Why is my Assignment Library empty when I create a Canvas assignment?
Your Assignment Library only shows the assignments you've created. Sign in to your Flat for Education account and create your assignments in the Assignment Library. The next time you open Flat for Education from Canvas, they'll all be there, ready to use.
Why isn't my Canvas assignment showing up in Flat for Education?
Open the assignment once from Canvas. This creates the linked copy of the assignment in your Flat for Education account, and it then appears in your account.
Can I see how long a student spent on an assignment?
Not at the moment. Flat for Education doesn't calculate the overall time a student spends on an assignment.
Grading
How do I reset a student's submission?
Open SpeedGrader, expand the grading window and click Reset Student Work.
Why isn't my worksheet graded automatically?
Automatic grading needs grading to be turned on in the Canvas assignment. Enable grading in your assignment settings in Canvas when you set up the assignment.
Why don't grades from Flat for Education show up in Canvas?
Grades are sent back for assignments created in Canvas. Create the assignment in Canvas and make sure grading is turned on in its settings. Students open the assignment from Canvas, which opens Flat for Education in a new window, and their grades are sent back to Canvas once you've graded their work.
How do I review submissions from cross-listed classes?
When classes are cross-listed in Canvas, the submissions from all of them are combined, which can make them harder to sort through. SpeedGrader helps you focus on one class at a time:
- Which submissions you see: SpeedGrader shows active student submissions based on your Gradebook settings. It can also show inactive enrollments, depending on your Gradebook configuration.
- One class at a time: in SpeedGrader you keep the familiar Flat for Education view and options, and you can choose a specific class to view.
To review one class:
- Open SpeedGrader in your Canvas course.
- Go to the Flat for Education window.
- Choose the class whose submissions you want to view.
Want to see it all in action? Watch our Canvas video tutorial series:
Still stuck? Our support team is happy to help you get Canvas working.
More questions and error messages
What does "Invalid LTI request signature" mean?
This LTI 1.1 error usually means the Shared Secret wasn't copied into Canvas correctly, for example because of a stray space or because the Key and Secret were swapped. Copy each value again, one at a time, from Settings > Integrations > Canvas, and paste it into Canvas. See the tip in the LTI 1.1 setup guide.
Why can't my students access their class or assignment in Flat for Education?
Usually, the teacher hasn't opened the class from Canvas yet. Before students can access it, the teacher needs to launch Flat for Education from within the Canvas course first, which creates the class in Flat for Education. Students then open the assignment, or Flat for Education in the course navigation, from Canvas, and they're signed in and added to the class automatically.
What happens when we move from LTI 1.1 to LTI 1.3?
Nothing changes for your existing assignments, classes and grades, as long as your students' email addresses haven't changed. Flat for Education recognizes each student by the email address Canvas provides, so their work stays linked after the switch. You can also test LTI 1.3 in one course before switching.