http://illuminations.nctm.org/LessonDetail.aspx?ID=U138
http://illuminations.nctm.org/LessonDetail.aspx?ID=L468
http://illuminations.nctm.org/LessonDetail.aspx?ID=L469
http://illuminations.nctm.org/LessonDetail.aspx?ID=U139
http://illuminations.nctm.org/LessonDetail.aspx?ID=L471
http://illuminations.nctm.org/LessonDetail.aspx?ID=L473
http://illuminations.nctm.org/LessonDetail.aspx?ID=L731
Line Symmetry - Nice set of examples
Rotation Symmetry - Nice set of examples
Point Symmetry - Nice set of examples
http://www.regentsprep.org/Regents/math/geometry/ GT1a/Lsymmet.htm
http://www.regentsprep.org/Regents/math/geometry/ GT1a/Rsymmet.htm
http://www.regentsprep.org/Regents/math/geometry/ GT1a/Psymmet.htm
Line Symmetry - Questions
Rotation Symmetry - Questions
Point Symmetry - Questions
http://www.regentsprep.org/Regents/math/geometry/ GT1a/PracSym.htm
http://www.regentsprep.org/Regents/math/geometry/ GT1a/PracRot.htm
http://www.regentsprep.org/Regents/math/geometry/ GT1a/PracPt.htm
http://www.illustrativemathematics.org/illustrations/1470
http://www.illustrativemathematics.org/illustrations/1471
https://www.youtube.com/watch?v=MpFfmDGPpVg
http://illuminations.nctm.org/ActivityDetail.aspx?ID=24
Determine the Rotational Symmetry of Regular Polygons
http://www.analyzemath.com/Geometry/ rotation_symmetry_shapes.html
http://www.analyzemath.com/Geometry/rotation_symmetry.html
Sheppard Software