Primary Resources
Primary Resources: 2 D and 3 D Shapes
Here is a huge collection of teacher resources for teaching 2-D and 3-D shapes. Includes smartboard and PowerPoint presentations, as well as worksheets and helpful hints.
Beacon Learning Center
Beacon Learning Center: Congruent or Not?
Students explore congruent polygons in this interactive web lesson.
The Math League
The Math League: Figures and Polygons
This site provides definitions of different types of polygons and figures.
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Rectas Notables De Un Triangulo
In Spanish. Interactive activities dealing with the concept of angle bisector, median and altitude of a triangle. A description of the circumcenter and centroid are given along with a visual representation. [Requires Java.]
CK-12 Foundation
Ck 12: Elem Math: Counting Rectangle,s Squares, Circles, and Triangles in Sets
[Free Registration/Login may be required to access all resource tools.] The video displays a set of figures and reviews triangles by number of sides. Then all of the triangles out of the set of figures are chosen. The video is followed...
CK-12 Foundation
Ck 12: Elem Math: Counting the Number of Different 2 D Shapes in a Set of Figures
[Free Registration/Login may be required to access all resource tools.] The video defines a triangle by the number of sides and then determines which of the figures in the diagram are triangles. The video is followed by additional...
![Pbs Mathline Lesson Plan: Mirror, Mirror [Pdf] Lesson Plan](https://d15y2dacu3jp90.cloudfront.net/images/attachment_defaults/resource/large/FPO-knovation.png "Pbs Mathline Lesson Plan: Mirror, Mirror [Pdf] Lesson Plan")
PBS
Pbs Mathline Lesson Plan: Mirror, Mirror [Pdf]
The goal of this PBS lesson is for young scholars to apply spatial reasoning, problem solving, and critical thinking skills to assess which regular polygons will tessellate. A detailed lesson plan that includes related worksheets, lesson...
PBS
Pbs: Mathline: Tessellations Wow! [Pdf]
An integrated geometry lesson on spatial sense in which young scholars identify and use different shapes to create a tessellation. "Through a variety of modalities such as writing, music, art, poetry, and literature, students are...
SEDL
The Timss Mathematics Segment: Geometry
This site explores the area of congruent triangles and how it is a difficult area to understand.
Curated OER
Nova Scotia Dept. Of Education: Mathematics 8: Geometry Diagrams
A collection of diagrams that complement Mathematics 8, a Grade 8 Math text, have been posted here. The diagrams were created using The Geometer's Sketchpad,
Texas Instruments
Texas Instruments: Cabri Jr. Getting Started With Triangles
This activity was developed as an introduction to the Cabri Jr. application on the TI-84 calculator. It investigates some basic properties of triangles. [Requires Adobe Reader.]
Texas Instruments
Texas Instruments: Walking the Fence Line, Then the Hypotenuse
In this activity, students use the Geoboard to determine the length of the hypotenuse of a right triangles. [Requires Adobe Reader.]
Texas Instruments
Texas Instruments: The Simson Line
Students study the Simson line and analyze the relationship it shares with its triangle. [Requires Adobe Reader.]
Texas Instruments
Texas Instruments: Math Today Dangerous Births
In this activity, using the USA TODAY Snapshot "Dangerous births" students will explore the geometric relationships of triangles using perpendicular bisectors of the sides, bisectors of the angles and medians of the triangle. They will...
Texas Instruments
Texas Instruments: Try Angle?
In this activity, students investigate properties of triangles by randomly generating possible side lengths for triangles. They learn to determine if three line segments can form a triangle. They also learn to classify triangles as...
Texas Instruments
Texas Instruments: Investigating Special Trangles
This activity will help students visualize the construction of these special triangles and find the ratios of the sides. It will help students later when they being trigonometry. [Requires Adobe Reader.]
Texas Instruments
Texas Instruments: Classifying Triangles by the Length of the Sides Using Cabri
This activity uses Cabri Jr. to classify triangles according to the length of their sides. [Requires Adobe Reader.]
Math Planet
Math Planet: Algebra 2: Trigonometric Functions
Get information about trigonometric functions by viewing examples and a video lesson. [2:08]
Math Planet
Math Planet: Algebra 2: Sines
Defines and examines the law of sines through examples and a video lesson. [2:02]
Math Planet
Math Planet: Geometry: Congruent Triangles
Features a definition and a video lesson on congruent triangles with examples. [1:11]
Scholastic
Scholastic: Study Jams! Math: Geometry: Classify Triangles
After completing the lesson on classifying triangles, you can sing along with karaoke and test your knowledge.
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Triangulos
In Spanish. This interactive activity shows how to compute the area of a triangle and the concept of altitude, median and angle bisector. [Requires Java.]
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Teselacion Del Plano
In Spanish. Gain your knowledge of tessellation with this interactive activity. Topics include identifying regular and semi-regular tessellations and figures that will tessellate. [Requires Java.]
Writing Fix
Writing Fix: Useful Shapes: Analytical Writing in Primary Math Classrooms
In this lesson, the book entitled The Greedy Triangle, written by Marilyn Burns, is shared. After sharing this read-aloud book, young scholars will illustrate pictures that incorporate the triangle. Then will write three reasons why a...