Text messaging (SMS) has been largely replaced by Instant Messaging yet 2011 showed over 2 trillion SMS worldwide (6 billion/day - compare with this chart to get a grasp of what exponential growth there's actually been). Carriers have now accepted the billions in annual losses from the switch, finding new sources of revenue - especially data sales. For a sample article of the current debate go here. http://www.engadget.com/2012/04/04/whatsapp-founder-versus-carriers/
Classifying Polygons practice or test - All squares are rectangles, but not all rectangles are squares. If your curriculum requires you to teach specific quadrilateral and triange concepts, you'll find this document to be very helpful.