Texas Instruments
Texas Instruments: Investigating Properties of Trapezoids
Students draw trapezoids and investigate their properties. They derive the area formula for a triangle from the area formula for a trapezoid. They also investigate the terms: Isosceles trapezoid and Tessellation. Numerous supplementary...
Texas Instruments
Texas Instruments: Investigating Properties of Trapezoids
This activity uses the graphing calculator to investigate trapezoids. Numerous supplementary materials are included. [Requires Adobe Reader.]
Math Open Reference
Math Open Reference: Quadrilaterals
A complete reference guide to quadrilaterals including squares, rectangles, parallelograms, trapezoids, and rhombus. It provides definitions and interactive activities that enhance further explanation.
Sophia Learning
Sophia: Coordinate Geometry of Trapezoids: Lesson 3
This lesson will demonstrate how to use slope, midpoint, and distance formulas to determine from the coordinates of the vertices if a quadrilateral is a trapezoid in a coordinate plane. It is 3 of 4 in the series titled "Coordinate...
CK-12 Foundation
Ck 12: Geometry: Trapezoids Grades 8 10
[Free Registration/Login may be required to access all resource tools.] Apply the properties of trapezoids.
CK-12 Foundation
Ck 12: Geometry: Trapezoids Grades 9 10
[Free Registration/Login may be required to access all resource tools.] This concept will teach students to use and apply the properties of trapezoids.
CK-12 Foundation
Ck 12: Elem Math: Visually Identifying Quadrilaterals
[Free Registration/Login may be required to access all resource tools.] Cursor down if needed to locate the video "Visually Identifying Quadrilaterals (Trapezoids, Parallelograms, Rectangles, Squares, Rhombi)." Students watch a video and...
CK-12 Foundation
Ck 12: Elem Math: Determining Unknown Angles in Trapezoids
[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on finding the missing angles in a trapezoid.
Better Lesson
Better Lesson: Finding the Area Review and Assessment
Sixth graders find the area of rectangles, triangles, parallelograms, and trapezoids by using formulas or by composing into rectangles or triangles.
National Council of Teachers of Mathematics
Nctm: Illuminations: Shape Tool
This tool allows you to create any geometric shape imaginable. Squares, triangles, rhombi, trapezoids and hexagons can be created, colored, enlarged, shrunk, rotated, reflected, sliced, and glued together.
OER Commons
Oer Commons: Gallery Problems Exercise
Students who have a clear understanding of the previous lessons can work on gallery problems of their choosing. This can be used as a good review or assessment.
Rice University
Rice University: Cynthia Lanius: No Matter What Shape Your Fractions Are In
Four basic geometric shapes - the triangle, parallelogram, trapezoid, and hexagon - are examined to determine how many of one shape fits "inside" another. For instance, how many triangles are "in" a hexagon. Ten questions with solutions...
PBS
Pbs Teachers: Architecture: Community Geometry
Identify architectural structures and objects in the community that represent different figures and types of geometry and mathematics.
Learning Wave Communications
Learning Wave: Geometry, Section 2
Geometry concepts are briefly discussed at this site, including volume of a cylinder, parallelograms, circles, trapezoids, and triangles. Sample problems and applications are included for practice.
University of Cambridge
University of Cambridge: Nrich: Count the Trapeziums (Trapezoids)
The challenge at this one page website, is to see how many trapezoids (British-trapeziums) you can find in the figure. When you have your results, you can easily check it right at the website.