If no quizzes are very few are available for you site, it may be because they have not been made available for use. The School Admin user needs to log on to Renaissance on the Administration Page https://hosted329.renlearn.com/61069/ and activate the quizzes.
To activate quizzes, go to the home page
Click once on the Accelerated Reader icon
Click on Manage Quiz Availability
On the next page click on Reading Practice
Click on the icon on the left that says show inactive quizzes
At the bottom of the list that appears, you can click activate all quizzes and all in the system will be available.