Samples from my most recent life drawing session. Basically there are three types of drawings- gestures, medium and long drawings. Gestures or gestural drawings are quick 1-2 min. sketches to get the gist of the pose (eg. the first photo). Long drawings are where you can go into detail and define the human form more clearly. We haven't really progressed to that stage yet.
Drawing the human figure is an ancient practice and actually a science- we deal with anatomy, measurement and proportion. Precision is key. If a foot is not placed at the right angle, it throws the entire drawing off. At the same time, it's definitely an art as one can show the spirit of the pose and even the model through expressive lines. One can experiment with different materials like charcoal pencil, graphite pencil and china marker and achieve a variety of styles. New models sometimes call for a new way of seeing and drawing. So far we've had a yoga practitioner, bodybuilder and baseball player. Somewhere down the line we'll have a ballerina I think.