The vocabulary for using oil pastels and teaching oil pastel techniques is very similar to that of hard or soft pastels. Here are some basic terms and concepts you can cover:

Outline

The artwork usually begins with a light outline that marks out where certain elements will appear in the composition. Usually a neutral color is used for this, depending on the colors that will appear in your artwork.

Underpainting

Most pastel artists start with an underpainting, which is often a monochromatic layer of pastel that fills in the outline. The underpainting starts to bring form and value to the composition. The underpainting is often blended before adding more pastel.

Blending

After applying the oil pastel to the paper, they may be blended by rubbing them with a finger, a folded paper towel, or by using a blending tool.

Layering

To achieve depth or create new colors, you must layer the oil pastels by placing a new layer on top of an old layer. Depending on what you are trying to achieve, the bottom layer can be blended before adding the new layer, or you can blend them both together.

Sgraffito

This is also known as the "scraping" technique and can be similar to the effects of scratch art.

One common sgraffito method is to make an underpainting of several bright colors, applied in a random, abstract manner. When finished, the colors may be lightly blended if desired. When the underpainting is finished, add a solid layer of oil pastel that completely covers the colorful bottom layer. Most people use black for the top layer, because it can adequately "hide" the bottom layer. Once the black layer is complete, you can use a scratching tool (shown below) to scrape away the top layer of black oil pastel, allowing the colors underneath to show through.

Wash

To create a wash similar to what you might achieve with watercolors, you can dip a paintbrush in turpentine or mineral spirits and run it over the oil pastel. This oil pastel technique can be used to quickly blend a layer of color.