How convex and concave mirrors work.
How to identify and describe reflectional symmetry.
Understanding reflection and refraction.
How lenses work.
How to determine the types of transformations, the definition of isometry, and how to say and write a transformation's new image.
How to describe a translation; how to interpret ordered pair rules.
How to define rotational symmetry and identify the degree of rotational symmetry of common regular polygons.
How to describe the effect of a reflection, how to describe the effect of the ordered pair rules (x,y) -> (-x, y),(x,y) -> (x, -y), (x,y) -> (y, x).