It is wonderful to have photos of models always available on your computer screen, smartphone, iPhone, iPad, or Android tablet from which to practice sketching whenever you have a few moments free. To sketch from sculptures as if they were models in a life drawing class, you can tour 17 art museums in the new Google Art Project and make your own collection of sculptured figures, or you can sketch from my Artwork Collection of 32 statues.
Above is my pen, ink, and wash sketch from the statue of Hebe, in the Alte Nationalgalerie, Berlin, as presented by the Google Art Project and as displayed on my Dell Streak 5 Android cell phone/tablet.
Above is my drawing of the statue of Diana, in the Metropolitan Museum of Art, New York, as shown on my daughter's iPhone.
My daughter, an engineer, added even more technology to this project by using the Brushes iPad App to sketch the image from her iPhone onto her iPad. She employed many layers to soften the shadows as she refined her drawing.
Artists have always sketched from live models in order to study the human figure, to refine their observations, and to practice drawing techniques. Live figures in action poses are the most desirable models, but this process of sketching from sculptures of human figures in action poses has it's own benefits. The models hold perfectly still, and the sketch artist can work as long as desired to study every aspect of the subject.
My son refers to devices such as the iPhone, iPad, and Android tablets as the ultimate sketcher's partners.