Teaching with Moodle

Thanks, John, I will try to explain in more detail.
In fact, Lesson itself is useless for grading, we are grading every activity included (via link) inside the Lesson (e.g. quizzes). So in the gradebook all quizzes are included in a category that has the same name as the lesson. In this way you are aggregating every activity included (via link) inside the Lesson and having a grade for the lesson

This is how the teacher sees the lesson with all the activities linked, the student only sees the lessson

This is how it is displayed in the grade book (teacher and students see the same)