https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-geometry-topic
IXL.com Q1; Q2; Q3
http://www.ixl.com/math/grade-6
https://learnzillion.com/lessons/1145-graph-points-in-any-quadrant
http://learnzillion.com/lessons/1146-write-coordinate-pairs-for-points
https://www.youtube.com/watch?v=OPkRvhEktTQ
