The "Focus Learning" tool is the reason why your class cannot access the different areas on the site. If you want your students to navigate freely on the site, please turn off this feature.
Log in and navigate to the Teacher Section. Once there, select the "Student Settings" option under the green "Classroom Tools" heading on the left of your screen.
The "Focused Learning" link is found in the upper-right corner of your screen.
You can use Focused Learning to limit access to the site for all students in your class. The toggle button at the top of the list allows you to turn this feature on and off. The three options below will be the only areas of the site students can use when turned on and switched to the color green.
Once selections have been made, click the blue "Save" button.