IXL

This tutorial explains how your IXL student rosters are created.

These tutorials will show you how to create quizzes and tests by using the IXL InstaQuiz Library of Questions and how to create quizzes by writing your own questions.

This link takes you to the IXL website's tutorial on how to use quizzes.  Scroll about halfway down the page to the section on assigning and managing quizzes.  This link will be in place until a tutorial with screenshots can be created.