Under the 6.NS.C.6 standard, this product practices part b in which students will:
"Understand signs of numbers in ordered pairs as indicating locations in quadrants of the coordinate plane; recognize that when two ordered pairs differ only by signs, the locations of the points are related by reflections across one or both axes."
This PowerPoint can serve as an introduction, or minilesson for students.
9 practice slides on reflecting across the y axis
9 practice slides on reflecting across t