Creating quizzes for your class is easy using CodeHS Custom Content. The Custom Content tool can found in the left sidebar of your teacher and class pages.
From there you can create a new course, or edit an existing one (once you have already created courses). This page also serves as your enrollment page, allowing you to un-enroll or re-enroll your classes in any of your custom courses.
Once created, you can select "Quiz" as the item time and click "Create Item".
Now we have created our quiz! From there you should enter your question text in the dialogue box and click "Save Quiz". Once saved, you can edit the "answer text" (what will be displayed as the answer option in the quiz) and the "message displayed upon answer" (the message that will appear when a student selects that option.
Once that quiz question has been fully set, be sure to save your question before creating another.
Once you have added all of your questions (and saved them), your quiz will be all ready for your students to take. To enroll a class in your custom course, revisit the first Custom Content page and click "Manage Classes" to the far right of your course name.
Once your class is enrolled, your students will see your custom course as a new course under "My Courses" (on the left sidebar of their user page. They can also click the "Switch Classes" button on their user page to access your custom course.