Microsoft Teams has Assignments app in Office 365 for Education License
If you have Office 365 Education License you can get Assignments Tab/app for creating assignments for your class.
I f you don’t have Office 365 for Education, you can get it for free for your faculty and students with a valid school email address.
To signup for Office 365 for education if you are in Faculty or School https://www.microsoft.com/en-us/education/products/office/default.aspx
Microsoft has also just released several updates to Assignments functionality:
- Easy to assign engaging learning activities
- Add assignment resources from any team
- See what your students see
- Add Close dates to your assignments
More about it can be found here