Interactive
National Council of Teachers of Mathematics

Nctm: Illuminations: Circle Area

For Students 3rd - 8th Standards
Explore what the relationship the radius has to the area of a circle. Click the instructions to learn how to use this interactive resource and select"Exploration" for more ideas.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Area and Volume of Similar Solids

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] In this lesson students find the ratios of the surface areas and the volumes of similar solids. Students examine guided notes, review guided practice, watch...
Activity
University of Regina (Canada)

University of Regina: Math Central: Surface Area to Volume Ratio

For Teachers 9th - 10th
Students will investigate the relationship between surface area and volume and their application to the inner workings of real life organisms.
Interactive
National Council of Teachers of Mathematics

Nctm: Illuminations: Scale Factor

For Students 3rd - 8th Standards
The interactive applet allows learners to explore the relationships between side length, area, and perimeter. Students see how changes in the scale factor influence the ratio of areas and perimeters. [Requires Java.]
Unit Plan
PBS

Pbs: Real World Ratio and Rate Reasoning: How to Power the Skate Park

For Students 6th - 8th
The CyberSquad works with area to figure out how to power a skate park using solar panels in this interactive from WNET. In the accompanying classroom activity, students view and analyze a series of video clips from Cyberchase and...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Area and Volume of Similar Solids

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to use ratios between similar solids to solve for missing information. Students examine guided notes, review guided practice, watch...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Area and Perimeter of Similar Polygons

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to find area and perimeter of similar polygons using ratios. Students examine guided notes, review guided practice, watch instructional...
Unit Plan
Sophia Learning

Sophia: Finding a Formula for the Surface Area of a Cone

For Students 9th - 10th
This video tutorial demonstrates how to find the formula for the surface area of a cone.
Unknown Type
University of Waterloo (Canada)

Centre for Education in Mathematics and Computing: Ratio and Rate [Pdf]

For Students 6th - 8th Standards
Learners explore the concepts of rate and ratio in a variety of problem-solving situations. Worksheets contain definitions and visual representations of concepts. Link to related ratio game. Other skills include measurement, data...
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Mg Hexagonal Pattern of Beehives

For Teachers 9th - 10th Standards
Beehives are made of walls, each of the same size, enclosing small hexagonal cells where honey and pollen are stored and bees are raised. This problem examines some of the mathematical advantages of the hexagonal tiling in a beehive....
Activity
National Council of Teachers of Mathematics

Nctm: Illuminations: Scale Factor

For Students 9th - 10th Standards
Use this applet to investigate how changes in the scale factor influence the ratio of perimeters and the ratio of areas between two figures.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Area and Perimeter of Similar Polygons

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] In this lesson students find the ratios of the perimeters and areas of similar polygons. Students examine guided notes, review guided practice, watch instructional...
Activity
TeachEngineering

Teach Engineering: A Chance at Monte Carlo

For Teachers 9th - 10th
At its core, the LEGO MINDSTORMS product provides a programmable microprocessor. Students use the EV3 processor to simulate an experiment involving thousands of uniformly random points placed within a unit square. Using the underlying...
Activity
Texas Instruments

Texas Instruments: Above and Beyond

For Teachers 9th - 10th
In this Computer Algebra System (CAS) activity, students create a general solution for calculating the ratio of the areas above and below a curve.
Activity
Texas Instruments

Texas Instruments: An Investigation in Calculus Using the Ti 92

For Teachers 9th - 10th
In this activity, students create a general solution for calculating the ratio of the areas above and below a curve.
Activity
Other

Desmos: Tile Pile

For Students 6th
Students explore proportional relationships in this activity as they build a ratio table in order to project how many tiles would be needed to cover the area of a floor.
Lesson Plan
Discovery Education

Discovery Education: Architects in Action

For Teachers 6th - 8th
Through this instructional activity, middle schoolers will learn how to use ratios to create a scale drawing of their classroom's floor plan. It provides adaptations, discussion questions, assessment rubric, and suggested readings to...
eBook
CK-12 Foundation

Ck 12: Interactive Geometry: 9.6 Density Problems

For Students 9th - 10th Standards
Density is a ratio of the mass/people/things to volume/area. Given the density and one of the two quantities in the ratio, solve for the other quantity in the ratio.
Lesson Plan
Alabama Learning Exchange

Alex: Circling Around

For Teachers 6th - 8th Standards
Students will calculate the diameter, circumference, and ratio of a real world object. Students will create an electronic slideshow to illustrate the process of determining the diameter, circumference, and ratio of these objects.
Activity
Texas Instruments

Texas Instruments: Circle Around

For Teachers 6th - 8th Standards
In this activity, students compute the circumference and area of circles. They understand that the ratio of the circumference to the diameter is a value called pi. [Requires Adobe Reader.]
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 6.rp Converting Square Units

For Teachers 6th Standards
In this task, 6th graders must inches to feet in order to find the area of a rectangular board and explain the error in the calculations made by the board owner. Aligns with 6.RP.A.3.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 6.g Painting a Barn

For Teachers 6th Standards
This task asks students to determine the area of the exterior walls of a barn and to calculate how many gallons of paint would be needed to cover them, as well as the cost of the paint. Aligns with 6.G.A and 6.RP.A.3.
Activity
Texas Instruments

Texas Instruments: Math Today Wing Tabs Save Fuel

For Teachers 9th - 10th
Using the USA TODAY Infograph, 'Wing tabs save fuel', ratios and proportions will be used to explore the concept of similarity between a drawing/model and the actual dimensions. The effects of dilation (size change) on an image and...
Handout
Math Open Reference

Math Open Reference: Similar Polygons and Triangles

For Students 9th - 10th Standards
A complete reference guide to similar triangles and polygons. It provides definitions and interactive activities that enhance further explanation.