*Parallelogram: *A parallelogram is quadrilateral that is characterized by two pair of opposite sides that are equal, and two pair of opposite angles that are equal.

** Rectangle:** A rectangle is a parallelogram with four right angles.

** Regular Polygon: **A regular polygon is a polygon that has congruent sides and angles.

** Square: **A square is a regular polygon with four 90 degree angles.

* Symmetrical:* A characteristic of an object or image that can be folded in half to create two identical sides.

**Acute Triangle: **An acute triangle is a triangle that has three acute angles that are less than 90 degrees.

** Obtuse Triangle: **An obtuse triangle is a triangle that has one obtuse angle that’s greater than 90 degrees, but less than 180 degrees.

*Right Triangle:** *A right triangle is a triangle that has one right angle that’s exactly 90 degrees. ** **

If I were to introduce this activity to my class, I would have them create individual Polygon Dictionaries as a unit project. For example, at the end of the unit, I would have students select six, two-dimensional shapes. Once their shapes were selected, I would incorporate the Frayer Model and have them define the shapes in their own words, provide an image of the shapes, as well as examples, non-examples, and characteristics.

Students would type the name of each polygon, and all of the criteria outlined above. They would arrange their dictionary in alphabetical order, one polygon per page, and eventually bind it together in a plastic cover. Students would be permitted to draw their own images, or they could find one on-line or in a magazine. Lastly, the outside of their dictionary must be decorated with a “polygon theme”. For example, they could tessellate the cover, draw a “character” made out of polygons, or merely draw a variety of polygons and spell out the word *dictionary*.

Since I teach 6^{th} & 7^{th} grade, I would require my 6^{th} grade to focus on 2-D shapes, while my 7^{th} grade focused on 3-D shapes. Student’s grades would be based on a geometry rubric, and they would also be required to write a reflection, in addition to submitting their dictionary. The reflection would require them to answer the following questions: Think about the polygons you selected for your dictionary. Where do you see these polygons the most in the real-world? What purpose do they serve? What can others learn by utilizing your dictionary?