Bowland
Design the Mascot
Explore how resizing an object affects its area. The set of lessons challenges young mathematicians to design a mascot for electronic devices. These designs undergo resizing to determine how scale factors of dilation affect area.
Under the Dome
Sphero Draw and Drive
Determine how far the ball rolled. The class watches a video of a person controlling a sphere rolling on the floor. Pupils develop some questions about the video and make estimates to the solutions of the questions. The teacher provides...
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.
Curated OER
Baseball Proportion
Eighth graders measure regular baseball bats and souvenir bats in centimeters. They determine how tall a person would be to be in proportion to the souvenir bat, create a poster depicting the person, and explain the proportional...
Curated OER
Proportions 1
In this proportion worksheet, students find the missing side of 4 shapes that are similar to their mate. Shapes include triangles and quadrilaterals,. In the second part of the worksheet, students use the scale factor to find missing...
Curated OER
Similar Figures
In this similar figures worksheet, students identify the meaning of similar, corresponding sides, and congruent. They use proportions to find the length of a missing side. Students dilate given figures according to a scale factor. ...
Benjamin Banneker Association
Celebrate Benjamin Banneker
Inventor, astronomer, surveyor, mathematician, clock maker. Learners celebrate the life of Benjamin Banneker by building creative analog clocks, making scale models, and solving problems related to surveying. The activities model the...
Curated OER
Maps
Students figure out the mileage from one state to another using a map. In this map instructional activity, students look at the scale factor and turn it into a fraction. They measure the distance between two cities and use the proportion...
EngageNY
Between-Figure and Within-Figure Ratios
Tie the unit together and see concepts click in your young mathematicians' minds. Scholars apply the properties of similar triangles to find heights of objects. They concentrate on the proportions built with known measures and solve to...
Noyce Foundation
Which is Bigger?
To take the longest path, go around—or was that go over? Class members measure scale drawings of a cylindrical vase to find the height and diameter. They calculate the actual height and circumference and determine which is larger.
Curated OER
Ratio and Proportion Word Problems
For this ratio and proportion worksheet, 8th graders solve 10 different word problems that include determining the ratio and probability of events described. First, they determine the ratio of hawks to crows in a cornfield. Then,...
Curated OER
Proportional Parts Homework
In this geometry learning exercise, students differentiate between similarity and proportion. They use scale factor as they solve for the different proportions. There are 15 questions.
PBS
Human Tree: Ratios
Create a personal tree. By visiting an exhibit at the National Museum of Mathematics, the resource introduces the idea of fractals. The exhibit takes an image of the person and creates a tree by repeating scaled images on the shoulders...
Curated OER
How Big is Barbie?
Students measure various dimensions of a male and a female dolls body and scale them proportionally to average human measurements. They calculate the appropriate scale factor (magnitude) to enlarge their doll and apply that scale factor...
Illustrative Mathematics
Cooking with the Whole Cup
Whoops! Travis accidentally put too much butter into the recipe. Your bakers must find out how to alter the recipe to accommodate different changes by using unit rates and ratios . The activity has multiple parts and calculations with...
Curated OER
Scale Me Down
Students create scale drawings, and ultimately scale models, of real-world objects in this Math lesson about ratios, proportion, scaling factors, and cross products. The lesson includes ideas for cross-curricular extensions and is...
Virginia Department of Education
Similar Solids and Proportional Reasoning
Double the dimensions, quadruple the surface area. Pairs build similar prisms and compare the ratios of their surface areas and volumes to the ratio of the heights. Given two similar cones, partners determine the ratios of the lateral...
Noyce Foundation
Photographs
Scaling needs to be picture perfect. Pupils use proportional reasoning to find the missing dimension of a photo. Class members determine the sizes of paper needed for two configurations of pictures in the short assessment task.
Curated OER
Dilation
Tenth graders identidy and define various geometry terms, Students create exact replicas of a shape that is either smaller or larger than the original shape. Students prove that their entire shapes are larger or smaller in the same...
Curated OER
Simplifying Ratios
For this simplifying ratios worksheet, 10th graders solve and complete 24 various types of problems. First, they complete each ratio and reduce when necessary. Then, students find the length and width of each rectangle described. They...
Indian Institute of Technology
Could King Kong Exist?
The title says it all: Could King Kong exist? Investigate how increasing the dimensions of an object affects its surface area and volume to mathematically conclude whether a creature with the weight and height of King Kong could actually...
EngageNY
Comparing the Ratio Method with the Parallel Method
Can you prove it? Lead your class through the development of the Side Splitter Theorem through proofs. Individuals connect the ratio and parallel method of dilation through an exploration of two proofs. After completing the proofs,...
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...
Chicago Botanic Garden
What Can Tree Rings Tell Us About Climate?
Tree rings are slightly thicker on the south side of the tree because it receives more sunlight. Part two in a series of five lessons helps learners analyze tree rings to determine the environmental conditions that caused size...