bohdanr561@yahoo.com
Subject: Summer PD
Chapter 5-1
Shadows Device Lesson Plan Template
Grade Level (circle one)
Format (circle one)
6
whole class
7
or
small group
What concept or idea is being developed in this lesson? Which case are you addressing? (underline 1)
Case 1 Height Shadow Constant-Distance to light/height of prop = constant
Case 2 Distance to Light is Constant-height of prop/ height of shadow = constant
Case 3 Height of prop is Constant-distance to light X Height of shadow = constant
What mathematical practice or standards are being addressed?
1. Make sense of problems and persevere in solving them.
2. Reason abstractly and quantitatively.
What CCSS are addressed?
1.
Understand the concept of a ratio and use ratio language to describe a ratio relationship between two
quantities.
3. Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about
tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.
a. Make tables of equivalent ratios relating quantities with whole number measurements, find
missing values in the tables, and plot the pairs of values on the coordinate plane. Use tables to
compare ratios.
Time 2 hrs
Essential question: How do you solve problems using ratio concepts and use ratio reasoning
Objective: Students will be able to understand the concept of a ratio and use ratio language to describe
a ratio relationship between two quantities
Vocabulary: ratio, equivalent ratio, constant
Materials: Shadow generator, props, Promethean board with flipchart, graph paper, table, yardstick,
lesson quiz
Activity or problems you will pose:
Part one
Familiarize students with variables: (distance from light, height of shadow, and height of prop) and
language
Place prop some distance from light have students measure distance from the light source, height of the
shadow, and the height of the prop. Repeat process with several other props to familiarize students with
the different measurements.
Next have students place small tree and large tree in some ways that produce a shadow of equal height.
Discuss what they are seeing. Then measure and record the distance from the light for each prop in the
table.
Prop
Height of prop
Small tree
Large tree
2
4
Distance
from light 1
Distance from
light 2
Distance from
light 3
Distance from
light 4
Repeat process 3 more times with a different shadow height each time.
Part 2
Analyze the relationship between the height of the props and the distances of the light from the props.
If you place the height of the small tree over the height of the large tree and compare that to the
distance from the light for the small tree over the distance from the light for the large tree and keep the
height of the shadow the same you should notice that the ratio is ½ for each. This should be discovered
by the students. Guide students to graph the results on the coordinate plane. X axis will be distances
from small tree y axis will be distances from large tree
Guiding questions:
What do you notice?
Can you see any relationships between the measurements?
Can you predict results from another (3rd) shadow height?
Academic language: The ratio of the distances from the light is equivalent to the ratio of prop heights.
Assessment:
Lesson quiz
Using what you know, If the small tree were placed 20 inches from the light source where would the
large tree need to be located in order to have the same shadow height?
If you place the small tree at 7 inches and the large tree at 13 inches will the shadows be the same
height? Explain why or why not