Due to an issue with the latest Chrome OS update, the "Apps" drawer is disappearing on the student Chromebooks when trying to access it for testing. We have developed a workaround until Google can fix the issue.
1. If you turn on the Chromebook and at this screen the "Apps" drawer is not available, select "Sign in with different account"
2. Once that is clicked, you will see the "Apps" drawer back in the Taskbar:
From there you can access the testing as usual.