A brief word on the review instructions. There are two longer practice periods of about fifteen minutes, in which we read over the two ideas and the associated comments, and then spend the bulk of the time with our eyes closed, "listening quietly but attentively" (W-pI.RII.In.3:1) for a message. Most longtime students of the Course agree that this does not mean we should expect to hear a voice, as Helen Schucman did, although some may. Messages can come in many forms: a feeling, an idea, an awareness without words. We are not used to sitting quietly just listening, and this is practice in doing so.
During the first half of the day we are to work with the first idea, and in the second half, the second idea. The shorter periods are not assigned any number; we are to continue the "frequent" applications of the previous lessons. If you take all the lessons in which a number is mentioned in regard to these shorter practices, the numbers average out to five per hour; I think we can assume that is about what is intended during these days of review.
Notice the seriousness attached to both the longer and shorter practices. I, for one, try to avoid the temptation to treat the review period as a time to slack off. This is what the author says:
Regard these practice periods as dedications to the way, the truth and the life. Refuse to be sidetracked into detours, illusions and thoughts of death. You are dedicated to salvation. Be determined each day not to leave your function unfulfilled. (W-pI.RII.In.5:1-4)
This is a course in mind training. Our minds will not be trained if we do not practice. We will not learn listening if we do not practice. This is what doing the Workbook is all about.