I used plain white construction/drawing paper and good old oil pastels. Trick is not to give the kids a pencil. Instead, we started with a black oil pastel and ended with a black oil pastel. I think this is the secret to ensuring the art will be done in a couple of session. Otherwise, children wielding pencils can become perfectionists very quickly.
Start the portrait by drawing a large letter “U” in the middle of the paper, then add the hair. I spend some time drawing on the white board showing the kids proper hair placement. Do the same for the facial features and before long, the kids will be ready to begin coloring their masterpieces.
Want to make the portraits spectacular? Encourage as much as you can, the importance of coloring in well. Also, add patterns to the background, instead of leaving it blank.
For A complete lesson tutorial, consider my “Fun with Portraits” Art booklet available for download.