The Waldorf curriculum moves into not just using art as the vehicle for the subject, but for bringing in the fine art of drawing of itself in the middle school and high school years. Different teachers seem to bring in charcoal drawing at different points, so like everything in the curriculum, this demands that you observe your child carefully and see when you think it is appropriate to start this journey. The Waldorf School Curriculum: An Overview for American Waldorf School Teachers (chart) lists:
Grade Six: exact geometric drawings, geometric string designs, mosaic pictures, black and white drawing, and shadows
Grade Seven: exact geometric drawing: two dimensional, to theorem of Pythagoras, areas of squares and triangles, perspective drawing, platonic solids, black and white drawing
Grade Eight: exact geometric drawing: three dimensional, theorems, volumes of solids, laws of logic, solid geometry, black and white drawing with charcoal
One book on drawing and painting that I highly recommend in this endeavor, for experienced Waldorf homeschoolers, is this one. It has a detailed series of pictures in charcoal to draw from and I found it invaluable in working with this medium this year.
I also found inspiration in these web resources:
This post was also a huge inspiration to me, and has a detailed supply list that I found to be very helpful: Sixth Grade Charcoal Drawings
A place we started was actually line drawings and then charcoal drawings of busts of the Roman Emperors/Charlemagne. This was recommended in the older edition of the Christopherus Roman History Guide. This worked well for both my daughter and I to be able to really see the shadows and start working on the beginnings of portraiture. Then we moved into the exercises in the book I linked to above.
I am looking forward to perspective drawing coming up this year in seventh grade, and especially how that relates to the human form in physiology. You can see how classical drawing builds on perspective drawing in books such as this one.