Recap
Acute, Right and Obtuse Angles
How to use a protractor
You can also learn how to draw an angle with a protractor from these site:
http://www.mathopenref.com/constdrawangle.html
http://www.mathsisfun.com/geometry/protractor-using.html
Parallel and Perpendicular Lines
Famous Paintings of Rectangles and Squares that are worth millions
Frank Stella Untitled 1967, magnificent Concentric Square Painting sold for $2 million