Activity
National Council of Teachers of Mathematics

Nctm: Illuminations: Cutting Corners

For Students 9th - 10th Standards
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.
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Classify Objects as Rectangles, Squares, Circles, or Triangles

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 classifying rectangles, squares, circles and triangles.
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Classify Objects as Rectangles, Squares, Circles, or Triangles

For Students 2nd - 4th Standards
[Free Registration/Login may be required to access all resource tools.] Students practice classifying various two dimensional shapes as rectangles, squares, circles or triangles.
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Classifying Real Life Objects as Basic 2 D Shapes

For Students 1st - 2nd Standards
[Free Registration/Login may be required to access all resource tools.] The video describes how to classify a real-world object as a circle, triangle, square or rectangle. The video is followed by additional practice problems.
Unknown Type
Khan Academy

Khan Academy: Classify Shapes by Line and Angle Types

For Students 3rd - 5th Standards
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.
Interactive
GeoGebra

Geogebra: Copy of Classify Two Dimensional Figures

For Students 4th - 6th Standards
User will drag the vertices of the quadrilaterals to decide on the best possible classification.
Unknown Type
Mr. Martini's Classroom

Mr. Martini's Classroom: Classifying Polygons and Finding Perimeters

For Students 3rd - 8th Standards
Assess learning of polygons and perimeters with this interactive multiple choice practice and quiz activity. Click the question mark for hints.
Unknown Type
Khan Academy

Khan Academy: Practice: Classify Shapes by Line and Angle Types

For Students 4th
Look at the properties of 2D shapes to see which shapes can belong to the same group. Includes hints.
Lesson Plan
PBS

Pbs Mathline Lesson: Geometry, It's a Perfect Fit [Pdf]

For Teachers 3rd - 5th Standards
This two-part geometry lesson plan has students identify, describe, and classify two-dimensional shapes. Students engage in hands-on activities including identifying shapes in the classroom, creating patterns with shapes, identifying...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Quadrilateral Classification

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to classify quadrilaterals in the coordinate plane.
Lesson Plan
Alabama Learning Exchange

Alex: What Do We Have in Common?

For Teachers 9th - 10th
This inquiry lesson explores the definitions of quadrilaterals and the properties of the diagonals of quadrilaterals to classify quadrilaterals. Students will work cooperatively to justify conclusions. This lesson plan was created by...
Handout
Math Is Fun

Math Is Fun: Regular 2 D Shapes

For Students 3rd - 8th Standards
This tutorial provides illustrations for regular 2-D shapes as well as a definition for polygons and for regular polygons.
Lesson Plan
Alabama Learning Exchange

Alex: Quadrilaterals

For Teachers 9th - 10th
This is an inquiry activity used to review Algebra 1 objectives by applying them to geometry concepts. Students explore the properties of quadrilaterals and classify them by definition. This activity can be use in geometry classes....
Website
University of Regina (Canada)

University of Regina: Math Central: Lesson: Mr. Z's 5 Minute Game of Geometric Pandemonium

For Teachers 3rd - 5th Standards
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...
Activity
NumberNut

Number Nut: Shapes, Symbols and Colors: Two Dimensional Shapes

For Students 3rd - 5th Standards
Describes, with illustrations, the basic two-dimensional shapes students will encounter in elementary Math.
Activity
NumberNut

Number Nut: Shapes, Symbols, and Colors: 2 D Shapes

For Students K - 1st Standards
Did you know that two-dimensional shapes are also called polygons? This lesson describes the various 2-D shapes and includes two interactive games to reinforce skills.
Whiteboard
ClassFlow

Class Flow: Two Dimensional Shapes Identify and Match

For Teachers Pre-K - 1st Standards
[Free Registration/Login Required] This flipchart helps students to analyze and compare various two-dimensional shapes according to the vertices, sides and parallel lines. It features "containers" created in Version 3 (can be used with...
Unit Plan
Khan Academy

Khan Academy: Identify Triangles by Angles

For Students 3rd - 5th Standards
Practice identifying triangles by their angles as acute, right, or obtuse. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Unit Plan
Khan Academy

Khan Academy: Identify Triangles by Side Lengths

For Students 3rd - 5th Standards
Practice identifying triangles by their side-lengths as equilateral, isosceles, or scalene. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Handout
Khan Academy

Khan Academy: Quadrilaterals Review

For Students 4th
After reviewing the properties of different quadrilaterals, students answer questions about each type.