At each lesson I assign multiple things for the student to work on that week. There are a few fundamental things like flow studies, lip slurs, and clarke studies. Then there are Etudes, solos, and contest music. Generally I assign 3-5 things.
Each week, I expect the students to work on everything that I assign. The next lesson we go over the assignments and I give a grade on the basis of work and improvement. Grades are A through C without minus or plus.
Some lesson teachers are happy to continue taking your money if the student isn't progressing, but I don't like that. If too many C's add up, I will discontinue lessons.
Here is how lessons are scored:
A: The student worked on everything I asked them to. They practiced efficiently and effectively. They made significant progress this week.
B: The student worked on some of the material, but not all of it. Or the student worked on all of it, but too little time to make a difference. Or the student spent a lot of time on it, but practiced incorrectly and didn't make progress.
C: The student came unprepared or underprepared. This week they wasted their parent's money.