the MET is free on 5th ave, drop tabs and hang out or just practice sketching. MOMA's free on Fridays and galleries are all open as long as you don't pull some IRAK moves.
http://chestofbooks.com/home-improvement/woodworking/Ira-S-Griffith/Courses-Woodwork-Mechanical-Drawing/images/Plate-51-Geometric-sheet-Drawing-Mechanical-Drawin-73.png
http://www.jimloy.com/geometry/pythag9.gif
"Kicking shit called street knowledge Why more niggas in the pen than in college?"