Teaching to Learn, Learning to Teach

QUESTIONS

1. What mathematical principles can help solve this
   problem?


2. What is the relationship between similar trian-
   gles?


3. Once we know that two triangles are similar, what
   is the relationship between corresponding sides?


4. What is the relationship between corresponding
   angles?

NOTES (OUTLINE)

1. When two triangles are similar, corresponding
   sides are in proportion.


2. When two triangles are similar, corresponding
   angles are congruent.


3. If we have information about the sides of one of
   the similar triangles, we can calculate information
   about the second triangle.

MEDIAL SUMMARY How can the properties of similar triangles help us discover the heights of very

tall objects?

QUESTIONS

1. How can we indirectly measure the height of the
   dead tree using a similar triangle?


2. If a 5 foot tall girl casts a shadow 4 feet long at the
   same time as the tree casts a shadow 20 feet
   long, how tall is the tree?

NOTES (OUTLINE)

1. Draw and label a diagram showing the triangles
   created by the girl and her shadow and the tree
   and its shadow.


2. Translate the diagram into mathematical notation
   and solve the problem. (5:X=4:20); (4X =
   100); (X = 25)


3. FINAL SUMMARY
   QUESTION

How can the properties of similar triangles help us solve the problem of the dead

tree?

4. APPLICATION Assign students additional problems to solve individually or in groups from the
   text book. Volunteers place additional problems on the board. Class reviews so-
   lutions.


5. HOMEWORK
   ASSIGNMENT

Assignment from textbook reviewing using properties of similar triangles to solve

problems.

II.c. Outline for a Developmental Lesson

AIM QUESTION/STATEMENT: ___________________________________________________

____________________________________________________________________________

PERFORMANCE OBJECTIVES (STANDARDS):

1._________________________________________________________________________

2._________________________________________________________________________

3._________________________________________________________________________

PREPARATION:

1. PREVIOUS HOMEWORK: ___

__________________________________________________________________________

2. PREVIOUS LESSON: ___

DEVELOPMENT:

1. MOTIVATION QUESTION: __

__________________________________________________________________________

78 CHAPTER 3