Lesson Plans / Progress Reports

Teachers,
When you go through multiple sessions with a student, do you give them a lesson plan?  Do you provide them with a planned progress report?  For example telling the student:
If we meet 3 times per week for 1 hour each time, after 4 weeks, you will have learned X, Y, & Z, and your conversational ability will have improved 10%

How do teachers & students convey expectations to each other?  How does the student know what they will learn?

Is this necessary?  Does it help to keep the student & teacher focused & on track?