If you click on Log in with Active Directory or Log in with Office 365 and the login page fails to load, trying clearing your cache. If accessing Clever from a Chromebook, we recommend signing out of the Chromebook and restarting the device. 

Here is more information directly from Clever if you are still having issues logging in.

https://support.clever.com/hc/en-us/articles/360000067006-For-Families-Troubleshooting-Logins-to-Clever