paper curl. Fun shading activity, different than the geometric shape drawings
How to draw an ellipse - from any angle (from http://www.idsketching.com/interesting-things/a-good-way-to-observe-ellipses/)
How To Draw A Cube In Perspective 3-point perspective vs. no
"How many licks" to the center of a Tootsie Roll Pop...
Image from http://media.tumblr.com/tumblr_m92jk38o7f1qd5yv1.jpg.
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