This workshop has the aim to recreate the perspective outline of the Music Lesson. The reader may notice in Figure 1, how the paintings image formation clearly fits in my RMS90 Modular Scale. We will learn the basic use of this scale to directly deduce all the elements of the scene in perspective. Therefore, neither a plan nor an elevation is required for the practice, just a good photograph copy of the painting is needed. I will provide these copies and the scales as well, while the participants should bring some A4 sheets, a portable drawing board, squares, eraser, and pencils (gray and yellow). It would take about 75 minutes to perform it. You will remember those high school days.