National Council of Teachers of Mathematics
Scale Factor
Does doubling mean everything doubles? Learners adjust the scale factor between two rectangles. Using the calculated measurements, pupils investigate the ratios between the lengths, perimeters, and areas of the rectangles.
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...
Curated OER
Geometry: Area, Scale Factor, Circumference
In this geometry worksheet, students solve 10 problems regarding area, scale factors, and circumference. Students, in 3 of the problems, are given the circumference and asked to work backwards to find missing information.
Curated OER
Geometry Worksheet 9.5: Rotational Symmetry
In this rotational symmetry worksheet, high schoolers solve 14 short answer and graphing problems. Students identify the order and magnitude of given figures. High schoolers find the scale factor of a dilation given a graph.
Curated OER
Scale Factor Area Perimeter
Mathematicians compare triangles at different scales. In this geometry lesson, students calculate the area and perimeter of triangles. They use the Ti to make observation of the change that takes place as the triangles are dilated.
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 strengthen...
Curated OER
Scale factors: Ratios and Proportions
Students create building and models using scale factors. In this geometry lesson, students apply the properties of ratio and proportion to solve problems. They identify the means and extremes property of cross multiplication.
Illustrative Mathematics
How Many Leaves on a Tree?
This is great go-to activity for those spring or fall days when the weather beckons your geometry class outside. Learners start with a small tree, devising strategies to accurately estimate the leaf count. They must then tackle the...
EngageNY
Making Scale Drawings Using the Ratio Method
Is that drawn to scale? Capture the artistry of geometry using the ratio method to create dilations. Mathematicians use a center and ratio to create a scaled drawing. They then use a ruler and protractor to verify measurements.
Curated OER
Exploring Similarity Using Scale Drawings
Learners explore scale factor as they create a scale drawing of a box, then determine the surface area and volume of the original and the scale drawing. The one page worksheet contains activities and procedures with four questions.
EngageNY
Scaling Principle for Volumes
Review the principles of scaling areas and draws a comparison to scaling volumes with a third dimensional measurement. The exercises continue with what happens to the volume if the dimensions are not multiplied by the same constant.
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
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 segments are...
Curated OER
Drawing to Scale
Students examine the process of drawing a picture to scale. They analyze and discuss real-life blueprints for a house, and create a scale drawing of an original invention using calculators and rulers.
Mathematics Vision Project
Module 7: Connecting Algebra and Geometry
The coordinate plane links key geometry and algebra concepts in this approachable but rigorous unit. The class starts by developing the distance formula from the Pythagorean Theorem, then moves to applications of slope. Activities...
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 and...
Curated OER
Dilations and Similarity
In this dilations and similarity instructional activity, pupils solve 10 different problems that include various dilations. First, they determine the scale factor of dilations found in the illustrated graphs. Then, everyone determines...
NASA
Oh, Chute!
Using a scare model of the a test vehicle developed by the Systems Architecture and Integration Office at NASA, groups determine the dimensions for a scale model of the parachute compartment. The groups also determine the volume of the...
Exploratorium
Measuring and Mapping the Playground
The school playground is a great place to learn about math. Pupils measure the dimensions of a playground using baby steps and individual strides. They use their measurements to create a scale drawing of the playground by applying an...
EngageNY
The Scaling Principle for Area
As they investigate scaling figures and calculate the resulting areas, groups determine the area of similar figures. They continue to investigate the results when the vertical and horizontal scales are not equal.
Curated OER
Transformations and Matrices
There are four activities in this extensive instructional activity covering the identity matrix and scaling, the linear representation of translations, the linear representation of rotations, and reflections. In small groups, they use...
Curated OER
Measure: Bearings and Scale Drawings
Pupils practice drawing geometric figures. In this geometry lesson, learners complete an activity that requires them to draw angles and shapes to the nearest degree.
Curated OER
A Geometry Worksheet - Similar Triangles
In this similar triangles activity, students find the scale factor of 6 sets of similar triangles. Students find the scale factor of two similar triangles given a sketch with measurements. Students use proportions to find a missing side...
Texas Instruments
What's the Scale?
Pupils will analyze scales as related to models and real life in this geometry lesson plan. They work together to compare the dimensions on a model as compared to the real building.