In Canvas you can set a material to "close" from and until certain dates by setting up the "Available from" and "Until" dates. Sometimes when you do this you need to unlock a material for a specific group of students.

Video Walk-Through:

https://player.vimeo.com/video/450229599

Step-by-Step Guide with Screenshots:

To unlock a material in Canvas: 1) Access the material's settings 2) Add another assign box and 3) Set a new "Until" date for the group of students.

1) Access the material's settings.

Click on the desired material.

Click on Edit from within the materials page in Canvas.

2) Add another assign box.

Scroll down in the material settings until you see the Assign to box.

Click on +Add at the bottom of the box to create another Assign to box.