Classifying Polygons
Pacing:This lesson should take one class period
Goal:This lesson explains the characteristics of a polygon. Students should be able to classify polygons according
to its number of sides and whether it’s convex or concave.
Language Arts Connection! Have students find several high school textbooks and internet sites that provide a
definition of polygon. Compare each definition for similarities and differences. Devise a workable classroom
definition of a polygon, using the ones found as guides.
Study Skills Tip! Flashcards are imperative to geometry success! Students should construct flashcards of the
important polygons. One side should be the drawing of the polygon with the reverse naming the polygon, listing the
number of sides, and if applicable the sum of the interior angles in a polygon or how to separate the polygon into
triangles (useful when determining polygonal area).
We love Pythagoras! When teaching the distance formula, relate this to Pythagorean’s Theorem. The vertical
distance (change iny) represents one leg of a right triangle and the horizontal distance (change inx) represents
the other leg. Usinga^2 +b^2 =c^2 , students can derive the distance formula. Many students will use Pythagorean’s
Theorem as opposed to the distance formula when determining the length between two points.
What Did You Learn? Use this activity as a culminating activity or perhaps an alternative assessment. Devise a
geometry scavenger hunt, listing the major concepts learned thus far. Equip students with a digital camera and their
imagination. Ask students to find as many objects as possible, capture them with a photograph and incorporate the
photos into a movie or slideshow presentation. Offer bonus points for such things as originality, nature made objects,
etc.
Problem Solving in Geometry
Pacing:While this concept should permeate throughout this course, this particular lesson should take one class
period.
Goal:Problem solving is necessary is daily life. Drawing diagrams, working backwards, checking multiple options,
and answering reasoning questions are imperative for students to learn. This lesson introduces the key questions one
1.1. Basics of Geometry