I've never worked in the medium of chalk until I became a Waldorf teacher. Several years ago, I witnessed a teacher at East Bay Waldorf masterfully create a chalk drawing on a blackboard with an Impressionist quality. I was hooked!
As I experimented with different techniques, I discovered I preferred Realism in depicting my subject matter. This series of drawings is of a performer in the Cirque du Soleil, which I used for my Human Anatomy class in the middle school. Here are a few helful hints on how to create a large scale piece.
Step One | Use a grid method. Traslating an image or photograph you like onto a blackboard is much easier if you scale it up with a grid, then draw in the outlines.
Step Two | Rough chalk in the larger shapes to give a base color, something neutral.
Step Three | Start layering chalk colors. The blackboard by virtue of being black gives an immediate depth to the work, so layering the colors becomes important to balance the black, allowing the colors to give the 3-dimensional quality.
Step Four | Identify areas where light is hitting your subject. This further makes the subject pop, as contrast is made with the black and surrounding colors.
Step Five | Add in detail chalk work. While layering the chalk involved the flat, long edge of the chalk, detailing will need the point end of the chalk.
Step Six | Create a background for your subject. Here, I decided to clean up the board by adding in more black chalk as it made the performer appear to be in a spotlight in a darkened space. The background should complement the subject, unless the whole board is used to create an entire landscape or scene.