Using scales (0 to 10, for instance) is a helpful way of measuring progress or testing the notion that "Nothing will change", and fostering Self-efficacy in that small changes are marked and even a small change implies some control, where perhaps none had previously been believed possible.
The use of a rating scale encourages externalisation of the problem, or reflection upon it in a way that fosters Mentalization.
When using rating scales it is important to RECORD the scores - ideally in a visual way such as a graph, but alternatively on a table. This can be positively reinforcing if a young person begins to see change 'in black and white'. It also emphasises the Cognitive Behavioural stance of therapist and client acting as joint enquirers/scientists, rather than expert and patient.
Stress management
Rating scales can also be used in more immediate stress management: spend some time getting a 0 - 10 scale "personalised" with short "portraits" of what a stress level 2, 3, 4...7, 8, 9 look like in this client. A sentence or two that gives an example of what that level of stress feels like will help a young person to "calibrate" how they are feeling against their own experience. Such a personalised scale could be printed out on a small card and carried around if that helps. Then specific relaxation techniques (such as Progressive Muscle Relaxation or techniques to manage Panic Attacks) or Anger Management approaches, can be tied to specific rating scores, giving the client a menu of possible responses.
Motivational work
Scales can also be used as a key technique in exploring and clarifying in Motivational Work: