Blind Continuous Drawing is a well known drawing practice but also a fun game under the right conditions. If you have artsy folk in your group (chances are you do) this is a game that will cater to their interests.

Supplies:

Paper
Fine Point Sharpie
Table

How to Play:

Have three students volunteer for this. One will model. Two will draw. Here's the rules: artists can't look down at their paper, nor can they lift their marker from the paper once they begin drawing. Let the group judge the best picture. They actually turn our pretty artistic looking when done right but it's definitely humorous to see how disfigured people become.

Pro Tips:

This can be used as a prize as well. We feature it on our "cell phone shootout" game in which students take a picture of images rolling via ppt. And they win what they've taken a picture of. So, they can win a portrait of themselves done by another student.
Don't pick young students. Most middle schoolers won't try to draw the person, they'll try to draw something funny and it turns out less interesting and less amusing.
You can play this game AND other drawing games on the same day. Like Pictionary for example. Check out our post on pictionary, we do it a bit awesomer-ly.