Academic Support FY08
625-B Summer 2008 Enhancement Grant
Standards-Based Module Planning
Professional Learning Community Grantees Product Template
Instructor(s) Name(s):
Stephanie Stockwell Smith
Dan Case
District/Organization:
Worcester
Learning Standards:
Geometry (10.G.6), Special Triangles
Guiding Principle I, II, IV, V
Activity: Special Triangles
Length of Time: 45 minutes +
Objective: Use 3 different methods to find the vertical height of an object.
Method 1: Ratios and Proportions
Finding the height of a flag pole
1. Measure height of one student and his shadow.
2. Measure height of flag pole shadow.
3. Student height
=
Flag pole height
student shadow height
flag pole shadow height
4. Solve.
Method 2: 30-60-90
1. Tape two pencils to a protractor, one at zero° and one at 60°.
2. Student stands next to flag pole and put a piece of tape onto flag pole at student eye level.
3. Hold the protractor up to student eye level and walk back until pencil at zero° is at tape
level on the flag pole and pencil at 60° is at the top of the flag pole.
4. Measure distance from where student is standing to the flag pole. This is the x value.
Multiply this value by the √3 and add height from ground to student eye. This is the
height of the flag pole.
x√3
Ground
Level
2x
Student
eye level
x
Method 3: 45-45-90
1. Tape two pencils to a protractor, one at zero° and one at 45°.
2. Student stands next to flag pole and put a piece of tape onto flag pole at student eye level.
3. Hold the protractor up to student eye level and walk back until pencil at zero° is at tape
level on the flag pole and pencil at 45° is at the top of the flag pole.
4. Measure distance from where student is standing to the flag pole. This is the x value. Add
height from ground to student eye. This is the height of the flag pole.
x√2
x
Ground
Level
Student
eye level
x
Assessment:
Teacher Observation
Next Steps:
Solve for x when given the length of two sides of a triangle.
Materials:
Measuring Tape
Pencils
Protractor