A 'Scale' is the criteria used to assess learning targets in Headrush. Scales are setup and managed via the Admin side of Headrush as part of each Learning Target set:

Each Learning Target set has one and only one Active scale, however each Learning Target Set can have a different scale (e.g.- Rubrics vs. Content):

These scales then show up in assessments as the criteria advisors, learners, and guest assessors use to evaluate the learners:

Every Learning Target can have its own unique scale level descriptors is you want. Often this is most relevant for rubrics or other complex learning targets:

Scale descriptors can be added as part of the Learning Target Upload or managed individually via the Admin Learning Targets editor. See Learning Target Setup for more details.