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Unit Plan
PBS

Accessible Shapes

For Teachers 6th - 8th Standards
All the 2-D and 3-D measurement work you need is in one location. Divided into three sections, the geometry lesson plans consist of visualization of three dimensions, classifying geometric figures, and finding surface area and volume....
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Assessment
Mathed Up!

Loci and Constructions

For Students 8th - 11th Standards
A General Certificate of Secondary Education math review has class members make basic constructions. Using a protractor and a ruler along with a compass, pupils develop drawings of triangles with given measurements. Scholars use their...
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Instructional Video3:08
Corbett Maths

Constructing SSS Triangles

For Students 8th - 11th Standards
Creating a triangles is as easy as 5, 6, 7. Using a ruler and compass to measure off lengths, a short video shows how to construct a triangle with three specific side lengths. The example creates a triangle with side lengths of 5 cm, 6...
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Instructional Video1:47
Corbett Maths

Constructing SAS Triangles

For Students 8th - 11th Standards
Two sides and an angle ... a triangle it makes. Given the measure to two sides and the angle between them, the narrator of a short video shows how to draw a triangle with a ruler and protractor. Pupils use handouts to practice the newly...
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Instructional Video2:22
Corbett Maths

Constructing ASA Triangles

For Students 8th - 11th Standards
The narrator of a short video explains the steps in constructing a triangle given the measure of two angles and the length of the side between the angles. The resource provides opportunities for pupils to practice the skill with two...
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Assessment
Concord Consortium

Orthogonal Circles

For Students 7th - 12th Standards
Here's some very interesting circles for your very interested pupils. A performance task requires scholars to sketch a pair of orthogonal circles so the centers are the endpoints of one side of a triangle. They draw an additional circle...
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Assessment
Concord Consortium

Isosceles Triangle Spaces

For Students 7th - 10th Standards
How many different types of triangles can your class name? A discovery lesson guides learners through an exploration of the different triangle types and the relationships between their angles and sides. Using coordinate geometry,...
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Assessment
Concord Consortium

In a Triangle

For Students 9th - 12th Standards
What's in a triangle? Just 180 degrees worth of angles! Young learners use given angle relationships in a triangle to write an algebraic representation. Using a system of equations, they simplify the equation to a linear representation.
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Assessment
Concord Consortium

Divisions

For Students 7th - 12th Standards
Divide and conquer the geometry problem. Young scholars consider how to subdivide triangles into smaller ones that have equal areas. They must apply their knowledge of medians to help accomplish the task.
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Assessment
Concord Consortium

Detective Stories

For Students 9th - 12th Standards
The truth will always come out. A short performance task has learners considering a witness statement given to a detective. They apply special line segments in triangles and Ceva's Theorem to prove that the witness is actually lying.
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Unit Plan
Mathematics Vision Project

Module 3: Geometric Figures

For Teachers 9th - 12th Standards
It's just not enough to know that something is true. Part of a MVP Geometry unit teaches young mathematicians how to write flow proofs and two-column proofs for conjectures involving lines, angles, and triangles.
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Assessment
Concord Consortium

Circling Trains

For Students 7th - 12th Standards
And round and round the park we go! Given a description of an amusement park with the locations of three attractions connected by walkways, learners consider what happens when additional attractions join the mix by doubling the length of...
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Assessment
Concord Consortium

Cities and Gas Stations

For Students 7th - 12th Standards
In Utah, one stretch of highway goes for 106 miles without a single gas station. Where should people build one? Scholars face the dilemma of where to place a new gas station between three cities. They consider distance and proximity to...
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Assessment
Concord Consortium

In Oz We Tryst

For Students 9th - 11th Standards
The shortest distance from point A to point B is a straight line, but measuring distance gets more complicated when there are three points! Given the location of three friends, individuals determine the best point for all three friends...
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Assessment
Concord Consortium

Triangles: Angle Space

For Students 9th - 12th
Three angles in a triangle, three-dimensional space, it all seems connected somehow. Given several different triangles, pupils use the three angles of the triangle as coordinates to plot points in three-dimensional space. They explore...
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Activity
Teach Engineering

Stay in Shape

For Teachers 7th - 9th Standards
Using their knowledge of right triangles, pupils find out how far a ship is from a light house. Class members determine how far around the world a ship would be sailing at a constant speed.
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Activity
101 Questions

Best Triangle

For Teachers 9th - 12th Standards
What makes an equilateral triangle equilateral? It turns out it's much more than just the side lengths! Learners analyze four different triangles to determine the best equilateral triangle. They create a formula that they later use to...
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Activity
DiscoverE

Dome Home

For Teachers 3rd - 8th
Homes come in many different shapes and sizes. Building a model of a geodesic dome is the ultimate goal for the activity. Cutting and folding is the way to go here.
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Interactive
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GeoGebra

Triangle Dilations

For Students 9th - 12th Standards
Stretch the class' knowledge of dilations. With the aid of the rubber band stretcher tool, learners perform dilations. They dilate the triangle by a whole number scale and a fractional scale from two centers of dilation.
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Interactive
CK-12 Foundation

Polygon Classification

For Students 8th - 10th
Polly want a polygon? Young mathematicians sort shapes using an interactive. They classify the shapes as convex polygons, concave polygons, or not polygons.
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Activity
Education Development Center

Finding Triangle Vertices

For Teachers 6th - 7th Standards
Where in the world (or at least in the coordinate plane) is the third vertex? Given two coordinate points for the vertices of a triangle, individuals find the location of the third vertex. They read an account of fictional...
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Lesson Plan
University of Minnesota

Try Angle

For Teachers 9th - 12th Standards
Does practice make perfect or just improvement? Scholars practice drawing a triangle on an Etch-A-Sketch. They learn about the part of the brain that controls sensory-motor integration and apply that to an analysis question.
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Interactive
CK-12 Foundation

Possible Triangles with Side-Side-Angle

For Students 10th - 12th
It's not often that math allows for multiple answers. Young mathematicians identify possible numbers of triangles when given two sides and a non-included angle. An interactive helps with this investigation.
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Interactive
CK-12 Foundation

Angle-Angle-Side Triangles: Garden Gate

For Students 10th - 12th Standards
Good fences make good gardens. Individuals use an interactive to see how angles and sides relate in a triangular-shaped garden fence. They apply the Law of Sines to find the length of the garden gate (third side of triangle) given two...