# Special angle pairs

29 teachers like this lesson
Print Lesson

## Objective

SWBAT identify special angle pairs and determine angle measurements.

#### Big Idea

Set the foundation for logical reasoning by providing basic proofs of theorems about complementary, supplementary, and vertical angles.

## Warm Up

10 minutes

Each day, students complete a Warm Up that usually consists of spiraling the previous day's material, in addition to older material.  Warm-up problems also sometimes extend lessons that students have encountered before to more unfamiliar contexts.

In today's warm-up, because it is the first lesson of a new unit, I review the Homework instead to maximize time in introducing a new concept.  The HW on a unit assessment day is generally spiraled review of previous topics, so it is a nice review of older material that improves retention over the course of the year.

40 minutes

## Huddle

10 minutes

For the huddle for this lesson, I really like to go over Silver Problem 5 in detail. The primary lesson I want them to learn is the elegant logical structure that underlies the whole endeavor of geometry.   I push students to not only identify the correct answers, but the logic behind each measurement. I also make clear that there is more than one way to prove the measure of each angle... another beautiful element in math.

In this particular problem, I really stress the vocabulary to identify each angle.  Getting kids fluent in the vocabulary of, especially, congruent and supplementary, is absolutely critical as this unit develops.  I keep pushing kids until they use the correct vocabulary, and then sometimes I even do an activity where I have kids close their eyes and I say something related to the definition, and they call out the vocabulary words.

For example:

Me: Angles that sum to 180 degrees.

Students: Supplementary!

Me: Angles that are opposite of each other and congruent.

Students: Vertical!

## Homework

15 minutes

HW89 Special angle pairs is to be completed at home and should take students approximately 15 minutes.