Education Development Center
Rectangles with the Same Numerical Area and Perimeter
Is it possible for a rectangle to have the same area and perimeter? If you disregard units, it happens! In a challenging task, groups work to determine the rectangles that meet these criterion. The hope is that learners will naturally...
Education Development Center
Choosing Samples
What makes a good sample? Your classes collaborate to answer this question through a task involving areas of rectangles. Given a set of 100 rectangles, they sample a set of five rectangles to estimate the average area of the figures. The...
CK-12 Foundation
Alternate Formula for the Area of a Triangle: Alternate Area of a Triangle
It's always nice to have a plan B. Pupils investigate an alternate formula for the area of a triangle that uses sine. A set of challenge questions shows how the new formula relates to the well-known formula of (1/2)bh.
CK-12 Foundation
Factorization of Quadratic Expressions: Algebra Tiles
What does it mean to factor the difference of two squares? The interactive presents an area model of the difference of two squares. Pupils rearrange the model to create a rectangular area. The learners determine the length and width...
CK-12 Foundation
Greatest Common Factor Using Lists: Tiling the Kitchen Floor
Use a combination of tiling a rectangle to find area and find the greatest common factor of the lengths of two sides and the area they create. Pupils increase and decrease the sides of the rectangle before answer five questions about...
EngageNY
Replacing Letters with Numbers
When did letters become the same as numbers? Scholars learn about substituting numbers for letters to evaluate algebraic expressions in the seventh part in a series of 36. The lesson plan focuses on expressions related to geometry, such...
CK-12 Foundation
Using Quadratic Equations to Solve Problems: Construct a Soccer Field
Determine whether the soccer field has the right area. Pupils create a virtual soccer field based upon constraints. They determine the equation that models the area and continue to investigate other potential areas.
EngageNY
Problem Solving and the Coordinate Plane
Class members investigate rectangles on the coordinate plane. They determine the length of line segments in the coordinate plane with the same x-coordinate or same y-coordinate and then solve geometric problems involving perimeter and...
Teach Engineering
Discovering Relationships Between Side Length and Area
Consider the relationship between side length and area as an input-output function. Scholars create input-output tables for the area of squares to determine an equation in the first installment of a three-part unit. Ditto for the area of...
Curriculum Corner
Academic Math Vocabulary
The ABCs of math are so important. Find commonly used math terms in a 42-page packet. Each page has the word, a place to write the definition, and a place to give specific examples of the term. A must-have for all math classrooms!
EngageNY
Solving Area Problems Using Scale Drawings
Calculate the areas of scale drawings until a more efficient method emerges. Pupils find the relationship between the scale factor of a scale drawing and the scale of the areas. They determine the scale of the areas is the square of the...
Noyce Foundation
Between the Lines
Explore linear and square dimensions by comparing areas of similar figures. A creative set of five activities designed for elementary through high school classes asks young scholars to compare areas of specific polygons. The first two...
Virginia Department of Education
Pythagorean Theorem
Investigate the meaning of the Pythagorean Theorem through modeling. After comparing the area of the square of each side, individuals cut triangles and squares to facilitate the comparison.
Teach Engineering
Scale Model Project
Try your hand at scale models. Scholars create a scale model of an object using a scale factor of their choice. As part of the project, they give presentations on their processes and calculations. This is the last installment of the...
Teach Engineering
Build the Biggest Box
Boxing takes on a whole new meaning! The second installment of the three-part series has groups create lidless boxes from construction paper that can hold the most rice. After testing out their constructions, they build a new box....
Noyce Foundation
Part and Whole
Now you'll never have trouble cutting a cake evenly again. Here is a set of five problems all about partitioning shapes into a given number of pieces and identifying the fractional amount of each piece. As learners progress through the...
Noyce Foundation
Poly-Gone
Investigate polygons from rectangles to triangles to octagons. Each level of the five-problem series targets a different grade level. Beginning with the level A problem, learners examine the relationship between area and perimeter by...
Noyce Foundation
Surrounded and Covered
What effect does changing the perimeter have on the area of a figure? The five problems in the resource explore this question at various grade levels. Elementary problems focus on the perimeter of rectangles and irregular figures with...
PBL Pathways
Total Cost to Produce the Turbo Blender
Class members blend their knowledge of functions and problem-solving skills to provide business advice to the Turbo Blender manufacturers. Through a project-based approach, learners examine marginal cost data to produce a function. They...
PBL Pathways
Lake Pollution
Explain the timing of a lake cleanup to the EPA using calculus. A project-based learning opportunity has learners compare rate functions to compute a total change. Their solutions explain the time needed to rid a lake of pollutants.
EngageNY
Real-World Area Problems
Not all structures take the shape of a polygon. The 21st lesson in a series of 29 shows young mathematicians they can create polygons out of composite shapes. Once they deconstruct the structures, they find the area of the composite figure.
Virginia Department of Education
The Pythagorean Relationship
Add up areas of squares to discover the pythagorean relationship. Small groups create right triangles with squares along each side. They calculate the areas of each square and notice the relationship. Groups construct other types of...
Virginia Department of Education
Area and Perimeter
Develop a strategy for finding the area and perimeter of irregular figures. Building on an understanding of finding area and perimeter of rectangles and triangles, learners apply the same concepts to composite figures. After practicing...
Mathed Up!
Area and Circumference of Circles
Don't go around and around, help your class determine amounts around and in a circle with a video that connects circumference to the perimeter or the distance around an object. The resource includes 14 questions dealing with circles and...