I work at a low income school and have developed my system so that every student gets a black belt (9 belts with 24 songs) and many go way beyond.
A big reason why they do this is that they are so motivated by the 70 extra belt songs that they can pass off.
You can get my black belt system for free here:
Some of my kids advance so quickly that I developed a huge pack of activities and 70 extra belts with charts for displaying what they have done on my outside bulletin board. All of the kids are so motivated to work on it. You can read about how I use the fast finishers are tutors here: Differentiating With Student Tutors in the Music Classroom
Here are preview pages of the Recorder Mega Pack: