Worksheet
Curated OER

Right Triangles

For Students 10th
In this right triangles worksheet, 10th graders solve and complete 12 various types of problems. First, they solve for x given each of the right triangles shown. Then, students determine the length of the shorter diagonal given the...
Lesson Plan
Curated OER

The Truth About Triangles And Proofs

For Teachers 9th - 12th
High schoolers engage in a lesson that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the...
Lesson Plan
Curated OER

Quandaries, Quagmires, and Quadrilaterals

For Teachers 3rd - 5th
Students classify, flip, slide, and turn a quantity of quadrilaterals.
Lesson Plan
Curated OER

Ovals, Rectangles, Squares, and Triangles

For Teachers 3rd - 5th
Students identify geometrical shapes displayed in photographs of everyday objects in a metropolitan setting.
Worksheet
Curated OER

Rounding

For Students 3rd - 4th
For this rounding worksheet, students solve 40 problems in which whole numbers are rounded to the nearest 10. 100 or 1000. Students also round to the nearest dollar.
Worksheet
Curated OER

Conditional Statements

For Students 11th
In this conditional statements worksheet, 11th graders solve and complete 15 various types of problems. First, they determine if a conclusion can be reached from the two statements using the law of detachment or the law of syllogism....
Lesson Plan
Curated OER

Equilateral Triangles

For Teachers 4th - 5th
Students examine the attribute of equilateral triangles. In this equilateral triangle lesson, students examine a number of paper triangles to determine how they are classified. They determine how triangles are depicted in Navajo rugs.
Lesson Plan
Curated OER

The Centroid : Balancing the History

For Teachers 10th - 12th
Young scholars discover the centroid of a triangle based on Euclid's constructions. They explore locus of points of a median. They understand properties of the segments that form the median and areas of the smaller sections formed by the...
Lesson Plan
Curated OER

The Plane! The Plane!

For Teachers 5th
Fifth graders work with polygons.
Lesson Plan
Curated OER

Pass It On

For Teachers 5th
Fifth graders participate in a class activity that helps them learn some geometric terms along with their definitions. They describe relationships between two and three-dimensional shapes and analyze attributes and properties of...
Lesson Plan
Curated OER

Exploring Special Segments in Triangles

For Teachers 9th - 12th
Students discover that four special segments have a common intersection point. They identify the position of the intersection point in triangles. They produce conjectures about areas of the divided triangles.
Lesson Plan
Oswego City School District

Regents Exam Prep Center: Angles and Triangles

For Teachers 9th - 10th Standards
On this site a viewer can learn about the different types of triangles, and categorized by either angles or sides. Tutorials are also included for interior and exterior angles of triangles. A teacher resource page includes a lesson plan...
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Classifying Right Obtuse or Acute by Angle Measure

For Students 3rd - 5th Standards
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on how to classify triangles based on angle measures.
Lesson Plan
Shodor Education Foundation

Shodor Interactivate: Lesson: Angles

For Teachers 3rd - 8th Standards
This upper elementary and middle school lesson plan introduces the concept of acute, obtuse and right angles. Also, as the lesson proceeds vertical, adjacent, alternate interior and alternate exterior angles are explored. Plenty of...
Handout
Oswego City School District

Regents Exam Prep Center: Geometry Vocabulary Resources

For Students 9th - 10th
A list of geometry definitions and a matching activity.
Unit Plan
CK-12 Foundation

Ck 12: Volume of Pyramids: Angle Exploration

For Students 4th - 8th Standards
[Free Registration/Login Required] Students explore classifying angles by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about the concept by...
Unit Plan
CK-12 Foundation

Ck 12: Volume of Pyramids: Right Angles in a Game of Pool

For Students 4th - 8th Standards
[Free Registration/Login Required] Students explore classifying angles by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about the concept by...
Lesson Plan
Homeschool Math

Homeschool Math: Lines, Rays, and Angles

For Teachers 4th - 5th Standards
This fourth-grade geometry lesson teaches the definitions for a line, ray, angle, acute angle, right angle, and obtuse angle. We also study how the size of the angle is ONLY determined by how much it has "opened" as compared to the whole...
eBook
Mathigon

Mathigon: Geometry: Triangles and Trigonometry: Properties of Triangles

For Students 9th - 10th Standards
This lesson focuses on the properties of triangles, a closed shape that has three sides, three vertices, and and three internal angles. There are different types of triangles such as a right triangle, obtuse, and acute based on the...
Unit Plan
CK-12 Foundation

Ck 12: Angle Classification

For Students 4th - 8th
[Free Registration/Login Required] Students explore classifying angles by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about the concept by...
Unknown Type
Khan Academy

Khan Academy: Angle Types

For Students 3rd - 5th Standards
In this exercise, students practice identifying angle types. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Interactive
Other

Visnos: Basic Angles

For Students 3rd - 8th Standards
Explore acute, obtuse, and angle measures in this interactive activity.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Angle Classification Grade 7

For Students 7th
[Free Registration/Login may be required to access all resource tools.] Classify angles as acute, obtuse, right or straight.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Angle Classification

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] Classify angles as acute, obtuse, right or straight.