How Should I Study Lessons?
In general, you’ll need to study a given lesson until you feel 80% comfortable with the material. You can then proceed to click Mark Complete. In the main pathways, there will be practice assignments following individual lessons or groups of lessons. You can take these practice assignments to confirm your understanding of the covered topics. Finally, you can also use core assessments and unit tests to check your knowledge and uncover your weak points in order to tackle them better.
On the primary lesson page, you will find an audio or video track of the instructional content. You can use this to learn new things and practice previously learned topics. On the lesson page, there are a number of practice tools. You can use the line-by-line audio and dialogue-only track to practice close listening and pronunciation modeling. Similarly, you can use the Review track to review vocabulary and phrases introduced in the lesson. The Vocabulary tool provides a review of the vocabulary in the lesson. Here you can use also create flashcard decks for more vocabulary practice. Finally, you can use the Lesson notes tool for an X-ray view of the instructional content of the lesson. The Lesson transcript tool allows you to zoom in on what was exactly said in the lesson.
See also this article for a full description of all the lesson materials.