Flipping/Reflecting
http://www.icoachmath.com/SiteMap/Flip.html
http://www.ixl.com/math/practice/grade-2-flip-turn-and-slide
http://www.learner.org/courses/teachingmath/grades3_5/session_02/section_02_a.html
http://www.ixl.com/math/practice/grade-2-flip-turn-and-slide
http://www.mathsisfun.com/geometry/reflection.html