This position is taught starting in my Introduction to Ballet class levels, to students who are at least 7-8 years old. Since many dancer students today take a very minimum of classical ballet class, they do not get the advantage of having their feet and legs strengthened and shaped by slow, careful, and repetitious work. Instead they are often pushed at a pace that is faster than ideal and the finer details of line and solid foundation get lost in the process. For this reason, in my classical ballet classes, I will always begin teaching sur le cou de pied and working from it, as opposed to using the conditional position or a flexed foot when it is a viable option. Once a student has the shape, strength and articulation to work from sur le cou de pied, moving to the conditional position or a flexed foot is easier than vice versa.
There are a progression of exercises to slowly and safely introduce this position to students aged 7/8 and up. It is very important that any strain felt in the foot, ankle, knee or hip be addressed as soon as it becomes known, since there are many joint movements involved and compensation in one will refer up or down the chain of the body. When my students transition into a blocked pre-pointe shoe and their actual pointe shoes - these progressions are re-visited, as needed, to encourage foot strength and articulation.
For all of these exercises begin standing facing the barre - preferably portable barres that are facing a mirror (unless you have mirrors behind your fixed barres).
Please note there are generally several weeks spent on each exercise before progressing to the next level. A huge part of the learning curve for students is their ability to maintain the correct alignment of the supporting side. The common challenges for the supporting side are maintaining turnout from the hip down and not hyper extending the supporting knee, as well as overall proper postural alignment.
Decrease the counts from Exercise 3 to 1 count per part.
Usually around Exercise 3 I begin to introduce the sur le cou de pied derrièrre using the same series of progressions as devant. The break down for that movement is:
After students are comfortable with both positions, the exercises for the position of sur le cou de pied are replaced with very slow petits battement preparation exercises and then also holding the shape of the foot while extending the leg to different positions pointe tendu.