EngageNY
Examples of Dilations
Does it matter how many points to dilate? The resource presents problems of dilating curved figures. Class members find out that not only do they need to dilate several points but the points need to be distributed about the entire curve...
EngageNY
Properties of Dilations
Investigate dilations to learn more about them. The second segment in a series of 16 provides a discussion of properties of dilations by going through examples. The problem set provides opportunities for scholars to construct dilations.
Balanced Assessment
House Plan
A short assessment has individuals determine the scale of a house plan. They use the scale to calculate the size of a door and window that need to be replaced, and then divide a bedroom in two, calculating the size of rooms created.
Balanced Assessment
Scale Charts
Develop scales using tables. Pupils complete charts to show equivalent scale factors before using the completed tables to determine the sizes of scale drawings. They finish the lesson and demonstrate their understanding by completing a...
EngageNY
Mid-Module Assessment Task: Grade 8 Module 3
How well does the class understand dilations? The three-part assessment presents problems related to the properties of dilations. Pupils perform dilations and determine whether a dilation is responsible for a specific image.
EngageNY
Fundamental Theorem of Similarity (FTS)
How do dilated line segments relate? Lead the class in an activity to determine the relationship between line segments and their dilated images. In the fourth section in a unit of 16, pupils discover the dilated line...
EngageNY
What Lies Behind “Same Shape”?
Develop a more precise definition of similar. The lesson begins with an informal definition of similar figures and develops the need to be more precise. The class learns about dilations and uses that knowledge to arrive at a...
Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Bowland
In or Out? ... What's Your Decision?
Young mathematicians use photos and video clips to determine if a cricket player is "in" or "out." This analysis occurs using scale factors, distance-rate-time formula, and consideration of precision and accuracy.
EngageNY
Matrix Notation Encompasses New Transformations!
Class members make a real connection to matrices in the 25th part of a series of 32 by looking at the identity matrix and making the connection to the multiplicative identity in the real numbers. Pupils explore different...
Balanced Assessment
Modern Building
Turn your pupils into emerging architects with a resource that asks learners to analyze a scale drawing of a building. They use the scale drawing to interpret the size of the actual building before recreating the drawing using a...
Balanced Assessment
How Big is Big?
Now you can create your own monster movie. Learners estimate the size of a scale model monster given comparison statements and analyze these estimates to determine if the scale model accurately portrays a lizard.
California Mathematics Project
Model Solar System
The sun's diameter is 864,337 miles—challenge learners to create a scale model of the solar system that fits in your classroom. Scholars make conversions and work with scientific notation as they create the scale model.
Teach Engineering
Using Map Scales to Figure Distances and Areas
The asteroid is getting closer and the question is whether the state of Alabraska is large enough for the shelter calculated in the previous activity. Teams determine the scale of their project and then use the scale on the map to...
Mathematics Assessment Project
Photographs
Picture your pupils using this assessment task. Class members must first determine the measurements of smaller copies of photographs placed next to the original. They then determine the dimensions of the entire sheet of photographs.
Teach Engineering
An Inflated Impression of Mars
Help your class understand the magnitude of the distance between Earth and Mars with an activity that asks small groups to use balloons to create scale models of the Earth, Moon, and Mars. Class members figure out the distances...
Journey Through the Universe
A Scale Model Solar System
Between the time scientists discovered Pluto and reclassified it as a dwarf planet, it did not even make one full revolution around the sun. In two activities, scholars investigate scale models and their properties. Pupils find that it...
EngageNY
How Do Dilations Map Angles?
The key to understanding is making connections. Scholars explore angle dilations using properties of parallel lines. At completion, pupils prove that angles of a dilation preserve their original measure.
EngageNY
Making Scale Drawings Using the Parallel Method
How many ways can you create a dilation? Many! Individuals strengthen their understanding of dilations by using various methods to create them. The new technique builds on pupils' understanding of the ratio method. Using the ratio,...
EngageNY
Scale Drawings
Are you searching for a purpose for geometric constructions? Use an engaging approach to explore dilations. Scholars create dilations using a construction method of their choice. As they build their constructed dilation, they...
EngageNY
Mid-Module Assessment Task - Geometry (Module 2)
Challenge: create an assessment that features higher level thinking from beginning to end. A ready-made test assesses knowledge of dilations using performance tasks. Every question requires a developed written response.
EngageNY
Dilations from Different Centers
Can you follow a composition of transformations, or better yet construct them? Young mathematicians analyze the composition of dilations, examining both the scale factor and centers of dilations. They discover relationships for both...
EngageNY
How Do Dilations Map Lines, Rays, and Circles?
Applying a learned technique to a new type of problem is an important skill in mathematics. The lesson asks scholars to apply their understanding to analyze dilations of different figures. They make conjectures and conclusions to...
EngageNY
Scale Factors
Is it bigger, or is it smaller—or maybe it's the same size? Individuals learn to describe enlargements and reductions and quantify the result. Lesson five in the series connects the creation of a dilated image to the result. Pupils...