Illustrative Mathematics
Illustrative Mathematics: G Co Fixed Points of Rigid Motions
A rigid motion of the plane is a map of the plane to itself which preserves distances between points. The purpose of this task is to use fixed points as a tool for studying and classifying rigid motions of the plane, i.e., translations,...
Khan Academy
Khan Academy: Congruence and Transformations
Given a pair of figures in the coordinate plane, try to map one onto the other and determine whether they are congruent. Includes examples of glide reflections. Students receive immediate feedback and have the opportunity to try...
Illustrative Mathematics
Illustrative Mathematics: G Co Seven Circles Ii
For this task, seven pennies are placed in a circle so that they are all touching one in the center and their neighbors. Students are asked to find as many rigid motions of the plane as they can which are symmetries of this configuration...
Texas Instruments
Texas Instruments: Flipping Over the Coordinate Plane
In this activity, students review basic geometry vocabulary while investigating reflections on a coordinate grid.
Oswego City School District
Regents Exam Prep Center: General "Transformation" Vocabulary
This site offers a short discussion of transformations. The discussion has few pictures and expresses the transformations in terms of relative coordinates rather than pictures.
National Council of Teachers of Mathematics
Nctm: Figure This: Upside Down (Pdf)
What lowercase letters read the same both upside down and right side up? If you have the answer, then you can handle this geometric symmetry math challenge. A one-page activity from the NTCM Math Challenge for Families collection....