University of Cambridge
University of Cambridge: Nrich: Where Are They?
Test your logic, polygon properties, and pattern recognition skills working on this challenge. Solution included.
Government of Alberta
Learn Alberta: Math Interactives: Exploring Shape Classification
Investigate the properties of triangles, quadrilaterals, and regular polygons using this interactive Learn Alberta math resource. Students are able to practice classifying shapes based on their different properties. Be sure to follow the...
Mathigon
Mathigon: Geometry: Angles and Polygons: Drawing Triangles
This lesson focuses on the Triangle Inequality, when the sum of the lengths of any two sides of a triangle is greater than the length of the third. When this happens, the three sides cannot form a triangle.
Math Open Reference
Math Open Reference: Hexagon (6 Gon)
Learn about hexagons with this resource which offers detailed explanations, examples, and an interactive. Subjects covered include properties of hexagons. Links to related topics.
Math Open Reference
Math Open Reference: Pentagon (5 Gon)
Learn about pentagons with this resource which offers detailed explanations, examples, and an interactive. Subjects covered include properties of decagons. Links to related topics.
PBS
Pbs Learning Media: Classifying Polygons
This interactive diagram focuses on sorting polygons by common properties and then you select the correct label for each section of the Venn Diagram.
Other
Antonio Gutierrez: Geometry From the Land of the Incas
Discovering the properties of constructions, seeing proofs in action, and viewing problems come to life here with this wonderful use of technology in the classroom. Single steps are explained and illustrated one at a time so that the...
National Council of Teachers of Mathematics
Nctm: Illuminations: Cutting Corners
Students will use their knowledge of plane figure attributes to create and view shapes by cutting and rotating shapes to stimulate discussions on names and attributes of various shapes they do not regularly encounter.
The Math League
The Math League: Figures and Polygons
This website has basic definitions for most polygons, regular and irregular.
University of Regina (Canada)
University of Regina: Math Central: Lesson: Mr. Z's 5 Minute Game of Geometric Pandemonium
Students make a series of geometric drawings of points, obtuse angles, rays, polygons, and the like. Each child is given one but not allowed to show anyone else. The drawing is then taped to the back of the child in front of them. The...
Calculator Soup
Calculator Soup: Regular Polygon Calculator
Use this calculator to calculate properties of a regular polygon. Enter any 1 variable plus the number of sides or the polygon name. Calculates side length, inradius, circumradius, area, and perimeter.
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Poligonos Regulares Y Circulo
In Spanish. This interactive site shows the properties of regular polygons and its elements.
CK-12 Foundation
Ck 12: Geometry: Parallelograms
[Free Registration/Login may be required to access all resource tools.] This concept teaches students properties of and theorems about parallelograms and how to apply them.
Khan Academy
Khan Academy: Identifying Quadrilaterals
Learn about the properties of rectangles, rhombuses, and squares, and practice identifying them. Includes hints for questions. CCSS.Math.Content.3.G.A.1 Understand that shapes in different categories
Math Is Fun
Math Is Fun: Regular 2 D Shapes
This tutorial provides illustrations for regular 2-D shapes as well as a definition for polygons and for regular polygons.
Wolfram Research
Wolfram Math World: Acute Triangle
This MathWorld site gives a short discussion on acute triangles with links to related terms and topics. The site offers a discussion on the least number of acute triangles to compose various polygons, and a discussion on the relationship...
Oswego City School District
Regents Exam Prep Center: Pythagorean Theorem
Who was Pythagoras and what is his theorem? Explore this concept and its relationship to the measurement of a right triangle in this test prep lesson plan. The lesson includes an interactive worksheet where students discover the answers...
Geometry Help
Geometry Help: Triangles
Explains the basic concept of triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
Khan Academy
Khan Academy: Classify Shapes by Line and Angle Types
Classify shapes based on pictures or attributes, such as angle types and side-lengths. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Analyze Math
Analyze Math: Regular Polygons
The interactive tutorial examines the properties and formulas of regular polygons, inscribed circles, and circumscribed circles.
BBC
Bbc: Bitesize: Maths: 2 D Shapes
Learn about the properties of 2-D shapes: circles, triangles, polygons, and quadrilaterals. Includes information, video, and examples about each, with games and quizzes for reinforcement.
Texas Instruments
Texas Instruments: What's the Angle?
Students discover properties of interior and exterior angles of convex polygons using the TI-89 and Geometer's Sketchpad.
National Council of Teachers of Mathematics
Nctm: Illuminations: Shape Sorter
Students learn how to categorize plane figure polygons using Venn Diagrams with this computer based tool.
Other
Ic Teachers: Shapes Quadrilaterals
Are you looking for a very basic website that will explain the basic properties of a quadrilateral? Use this site to learn about the properties of a square, rhombus, rectangle, parallelogram, trapezoid, and kite. There are also some...