Illustrative Mathematics
What is a Trapezoid? (Part 2)
This collaborative activity investigates the meaning of a trapezoid and a parallelogram. It begins by presenting two different definitions of a trapezoid. Learners are to reason abstractly the difference between the two definitions and...
Illustrative Mathematics
What is a Trapezoid? (Part 1)
Challenge your class to construct a definition for trapezoids. Looking at four examples and four non-examples, students individually create definitions and use them to classify an unknown shape. Allow for small group and whole-class...
Curated OER
Developing Formulas for Triangles and Quadrilaterals
In this geometry worksheet, 10th graders determine the area of triangles, parallelograms, trapezoids, kites, and rhombuses. The one page worksheet contains eleven problems. Answers are included.
Curated OER
Properties of Parallelograms
Young scholars identify different properties of parallelograms. In this geometry lesson, students complete problems that proves the theorems and properties of parallelograms. They graph the different shapes on paper.
Curated OER
Why Do We Add The Bases To Find The Area of A Trapezoid?
Students are given patterns of trapezoids and are to calculate the area of one trapezoid by using both patterns. They should form a parallelogram and calculate the area. They practice this technique until there is understanding.
Curated OER
Perimeter & Area Worksheet I
For this perimeter and area worksheet, learners find the perimeter and area of regular polygons. They identify the perimeter and area of polygons such as triangles, trapezoids, circles, rectangles, and parallelograms. Students write the...
Curated OER
The Trappings of Trapezoids
Learners define trapezoids and their shapes. In this geometry lesson, students calculate the area of a trapezoid and a parallelogram. They use Cabri software to make investigations.
Curated OER
An Introduction to Quadrilaterals
Students explore the concept of quadrilaterals. In this quadrilateral lesson, students play with a floor tile applet to see that there are many types and characteristics of quadrilaterals including parallelograms, trapezoids, rectangles,...
Government of Hong Kong
Areas and Volumes - 2D Shapes
Unfortunately for young mathematicians, the world isn't made entirely of parallelograms, triangles, and trapezoids. After first learning the area formulas for these common shapes, students apply this new knowledge to determine the area...
Willow Tree
Area of Common Geometric Figures
Scholars can use area formulas, but can they apply what they know about area? The lesson plan challenges learners to think logically while practicing finding area of shapes such as rectangles, circles, parallelograms, triangles, and...
Curated OER
Areas of Trapezoids, Rhombuses and Kites
Students calculate the area of different polygons. In this geometry lesson, students find the area for trapezoids, rhombuses and kites.
Curated OER
Area Formulas
Students use the area formula for a rectangle to identify the area formulas for triangles, parallelograms, and trapezoids. In groups they complete a variety of worksheets, and examine irregular figures whose areas can be determined by...
Curated OER
Polygons, Parallelograms, Quadrilaterals- Oh My!!!
Students demonstrate their comprehension of shapes and their properties. They work in small groups. Students review the following terms: property, polygon, quadrilateral, and parallelogram. They read Shape Up! Fun With Triangles and...
Curated OER
Area of Parallelograms
Seventh graders review the process of finding the area of a rectangle and complete a couple of examples as a class. They discuss what a parallelogram is and what the formula would be for finding its area. They listen to an explanation...
Curated OER
Tricky Traps
Students create identify properties of trapezoids. In this geometry instructional activity, students calculate the area of given trapezoids and review the area formula for parallelograms. They draw a correlation between the area of a...
Curated OER
Algebra/Geometry Institute: Area of Polygons
Students find the area of polygons. For this area of polygons lesson, students find the area of parallelograms, rectangles, squares, and other polygons. They identify each given figure and determine the appropriate formula needed to...
Curated OER
Investigation-Looking at Polygons
Eighth graders plot points and investigate polygons. They locate a point, using ordered pairs of integers on the coordinate plane. Students compare geometric measurements and computations on coordinate axes as they are applied to...
Curated OER
Properties of Special Parallelograms
Students identify properties of trapezoids. In this geometry lesson, students are put into groups and use computer programs to analyze polygons. They drag and move the shapes around as they make predictions.
Curated OER
Classifying Quadrilaterals
Students cut out three different shapes and put them in the correct categories of parallelograms, trapezoids, and trapeziums. In this parallelogram lesson plan, students explain the sums of the angles of a triangle and a quadrilateral.
Curated OER
Can You Make Quadrilaterals?
Students identify and describe squares, rectangles, parallelograms, trapezoids, and kites. In this quadrilaterals lesson plan, students put the quadrilateral shapes into a chart.
Curated OER
Investigating Area Relationships
Learners investigate the area of various figures. They construct triangles and quadrilaterals using Cabri Jr. and discuss the relationships between different angles, side lengths, and figures.
Curated OER
Quadrilaterals
Students construct a variety of four-sided figures using a K'NEX Geometry Set. They view and discuss pictures of shapes, then in small groups they construct as many four-sided shapes as possible using the K'NEX Rods and Connectors. As a...
Illustrative Mathematics
Lines of Symmetry for Quadrilaterals
Explore how lines of symmetry help define different categories of quadrilaterals. Looking at a square, rectangle, trapezoid, and parallelogram, young mathematicians discover that each shape has its own, unique symmetry. Encourage your...
Curated OER
Finding the Area of Shapes
In this area of shapes unit, upper graders participate in hands-on problem solving activities to find the formulas for the area of a parallelogram, a triangle, and a trapezoid. They manipulate the geoboard to explore relationships among...