Scales are similar, but not the same as rubrics. Generally, most rubrics are based on a 100 percentage point range. Based on what a student demonstrates with the assignment, the teacher uses the rubric to determine how many points--which equal a percentage of the total possible--the student has earned. Often, rubrics show a student what has either been done or what hasn't been done (note the language of the descriptions of the lower scoring components of a rubric; this language usually speaks to what a student failed to do, and the language is in a negative tone).
Scales vary in that they are not focused on what percentage of the whole has been demonstrated, but rather on what level of learning has been demonstrated. Scales indicate the progression of learning towards the learning outcome, list the qualifying criteria, and may also describe what a student is able to do if they are demonstrating learning at that level in a more concrete manner. Scales act more as a map towards the learning outcome than as a tool for grading.
One of the key components of standards based learning is that it is concerned with the progression towards a learning outcome (standard). In order for there to be a progression, we need to be able to define various levels or stages or benchmarks along the continuum of learning. We usually look at these as four to seven distinct levels in a person's learning as they move towards--and perhaps beyond--the defined learning objective.
Emerging (1) is where a learner takes the initial steps towards the learning objective. Often this is where becoming familiar with what the learning objective really is (vocabulary is crucial here). This is the foundation for moving forward in one's learning; this is how students' begin to establish prior knowledge that will continue to help them along the way. It is also essential that students and instructors develop a shared sense of the key terms that they will be using as they move forward in the learning progression.
Developing (2) is where students begin to recognize the outcome, or the components that contribute to achieving the outcome, in other examples. They may also begin practicing, or even applying with help from the instructor. This is the level where students will spend the majority of their time in the cycle of observing, understanding, practicing, receiving feedback, and trying again.
Proficient (3) is where students have mastered a learning objective. They have truly learned it!!!! Not only is this the goal for every student, but this is challenging and difficult and very personal/individual for each person. Let's be honest, we all didn't learn to ride a bike, or write an essay, or solve a complex problem in the same way or in the same amount of time.
Students here are applying the learning in a very real way, and can do so without help (IEP's will be an exception here). This is where students are synthesising the learning in a very real, and permanent manner.
Advanced (4) is when a learner can truly go beyond--and extend--the learning objective in new and unique ways. A student may be able to teach and facilitate the learning of others in respect to the learning objective, or apply the skills and knowledge of the learning objective in new and unique ways. If the goal was to be able to slam dunk a basketball, an advanced demonstration could be reverse dunks, freethrow dunks, alley oop dunks, etc.
This is a general way to start playing with learning scales, but by no means is this the way. While scales are at their best when they are uniform between teachers regarding the specific learning outcome, it makes sense to start with them on a personal level.
With practice and understanding, a scale can be written on the board in a short time so that all students can see it. Or saved and printed in a hand out. In this way, students can see where they are, what they have already accomplished, and what they need to learn next. The idea is to focus on the learning, and the progression of learning, and not the grade one receives on an assignment or task.