Curated OER
Pythagorean Theorem by Graphic Manipulation
There are many different ways to show a proof of the Pythagorean Theorem. Here is a nice hands-on paper cutting activity that shows a graphic representation. You can even challenge your young Pythagoreans to come up with their own...
Curated OER
Rounding
In 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.
Curated OER
Equilateral Triangles
Students examine the attribute of equilateral triangles. For 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.
Curated OER
Vocabulary Challenge
In this math vocabulary worksheet, students choose which multiple choice answer best defines twenty-five mathematical terms. Students place their answers on the lines provided.
Curated OER
Geometry House!
Fourth graders use computer drawing tools to create a house of geometric shapes.
Curated OER
Geo-Mat
Students review plane figures by playing a game that resembles "Twister." They listen to directions to locate a large example of the figure which is placed on the floor.
Curated OER
Exploring Special Segments in Triangles
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.
Khan Academy
Khan Academy: Draw Right, Acute, and Obtuse Angles
Create an acute, right, or obtuse angle using a given vertex. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Draw Right, Acute, and Obtuse Angles
Create an acute, right, or obtuse angle using a given vertex.
CK-12 Foundation
Ck 12: Elem Math: Classifying Angles as Right, Acute, or Obtuse
[Free Registration/Login may be required to access all resource tools.] In this learning module, students are presented with angles and must identify what type each is. An accompanying video demonstrates a sample problem. [2:10] A set of...
Better Lesson
Better Lesson: Finding Angles
The three types of angles, right, acute, and obtuse, exist in our everyday surroundings. Students find these angles using classroom items.
ClassFlow
Class Flow: Angle Tester
[Free Registration/Login Required] This flipchart reviews right, acute and obtuse angles with students. An Activote review is included at the end.
ClassFlow
Class Flow: Angles Votes
[Free Registration/Login Required] Using this flipchart, students will be able to identify various angles based on mathematical criteria. Questions are related to right, acute, and obtuse angles.
Alabama Learning Exchange
Alex: Angle Scavenger Hunt
In this lesson, students will explore straight, right, acute, and obtuse angles. Students will go on a scavenger hunt throughout the school to search for examples of these types of angles. The students will use digital cameras to record...
Oswego City School District
Regents Exam Prep Center: Angles and Triangles
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...
Homeschool Math
Homeschool Math: Lines, Rays, and Angles
This fourth-grade geometry lesson plan 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...
Analyze Math
Analyze Math: Angles in Geometry
Definitions and properties of angles in geometry are explored. Topics discussed are right, acute, and complementary angles. Practice exercises with solutions are included.
ClassFlow
Class Flow: Angle This Way
[Free Registration/Login Required] Students will identify right, acute and obtuse triangles using many interactive tools available in ACTIVstudio 3.0. Students will be engaged using a magnifier tool, the fill tool, and drag and drop and...
Math Open Reference
Math Open Reference: Angles
Everything you wanted to know about angles and more, including 1) how to measure angles 2) types of angles 3) angle relationships and 4) angles around a transversal.
CK-12 Foundation
Ck 12: Elem Math: Classifying Right Obtuse or Acute by Angle Measure
[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.
Mathigon
Mathigon: Geometry: Triangles and Trigonometry: Properties of Triangles
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...
Math Is Fun
Math Is Fun: Angles
Definitions of different types of angles along with images and an interactive tool through which you can create acute, right, straight, obtuse, and reflex angles. View the parts of an angle, and learn the proper way to label angles.
Shodor Education Foundation
Shodor Interactivate: Lesson: Angles
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...
Texas Instruments
Texas Instruments: Classifying Angles
Students will create a variety of angles using the Geoboard APP. The teacher will use Screen Capture to display the angles created by the students and will lead a discussion on whether the angles are acute, right, or obtuse.