Curated OER
Quadrilateral Attributes
Students classify quadrilaterals. In this quadrilateral lesson plan, students identify the characteristics of quadrilaterals. They write their findings in a journal. Students use geoboards to create quadrilaterals from given descriptions.
EngageNY
Cyclic Quadrilaterals
What does it mean for a quadrilateral to be cyclic? Mathematicians first learn what it means for a quadrilateral to be cyclic. They then investigate angle measures and area in such a quadrilateral.
Illustrative Mathematics
All vs. Only Some
All shapes have certain defining attributes that set them apart from others. In order to understand this, young mathematicians look at examples and non-examples of triangles, rectangles, and squares, working as a whole class to create...
Curated OER
Investigating Quadrilaterals
Fourth graders discuss the various attributes of quadrilaterals. In groups, they use the attributes to sort quadrilaterals into different classes and a hierarchy. They review the new vocabulary and attributes with a partner to end the...
Illustrative Mathematics
What Shape Am I?
Sharpen your pencil and grab a ruler, it's time to draw some quadrilaterals! Given the definition of a parallelogram, rectangle, and rhombus, learners draw examples and nonexamples of each figure. The three definitions are then used to...
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...
EngageNY
Ptolemy's Theorem
Everyone's heard of Pythagoras, but who's Ptolemy? Learners test Ptolemy's Theorem using a specific cyclic quadrilateral and a ruler in the 22nd installment of a 23-part module. They then work through a proof of the theorem.
Math Solutions
Shape Sorting: Looking for Green!
Young mathematicians rotate, flip, and sort their way to an understanding of the different attributes of geometric figures. Using transparent yellow and blue shapes, children try to match congruent figures together to create...
Curated OER
Geometry: Classifying Quadrilaterals
Students use construction technology to identify and find relationships between the attributes of various quadrilaterals. They make and test conjectures about the distinguishing properties of parallelograms, rectangles, rhombuses,...
Curated OER
Rectangles and Parallelograms
Students compare parallelograms and rectangles. In this comparing parallelograms and rectangles lesson, students make a chart to compare parallelograms and rectangles. Students are given set of quadrilaterals and they must classify...
Curated OER
Geometry is Fun and EverywhereGeometry, You Don’t Care? Geometry is Fun and Everywhere
Third graders investigate shapes in our world. In this geometry instructional activity, 3rd graders describe plane and solid shapes and identify angles, solid objects and lines of symmetry. Students use online resources, graphic...
EngageNY
Perimeter and Area of Polygonal Regions Defined by Systems of Inequalities
When algebra and geometry get together, good things happen! Given a system of inequalities that create a quadrilateral, learners graph and find vertices. They then use the vertices and Green's Theorem to find the area and perimeter of...
Noyce Foundation
Lyle's Triangles
Try five problems on triangles. Levels A and B focus on shapes that can be created from right triangles. Level C touches upon the relationship between the area of a six-pointed star and the area of each triangle of which it is composed....
Education Development Center
Finding Parallelogram Vertices
Four is the perfect number—if you're talking about parallelograms. Scholars determine a possible fourth vertex of a parallelogram in the coordinate plane given the coordinates of three vertices. They read a conversation...
Curated OER
Origami Cubes
Fourth graders use an origami design to make a set of cubes. Individually, they identify the characteristics of different quadrilaterals as they are folding the paper into cubes. To end the lesson, they make a new design with new...
Curated OER
Meet the Polygon Family
Fourth graders investigate regular polygons. In this regular polygon lesson, 4th graders explore the attributes of different polygons. Students work in groups to complete a KWL chart regarding polygons.
EngageNY
Perimeter and Area of Polygonal Regions in the Cartesian Plane
How many sides does that polygon have? Building directly from lesson number eight in this series, learners now find the area and perimeter of any polygon on the coordinate plane. They decompose the polygons into triangles and use Green's...
EngageNY
Are All Parabolas Similar?
Congruence and similarity apply to functions as well as polygons. Learners examine the effects of transformations on the shape of parabolas. They determine the transformation(s) that produce similar and congruent functions.
Curated OER
Patterns in the Sums of Polygon Angles
Sixth graders discover the patterns of sums of polygon angles. In this math lesson, 6th graders study the properties of geometric shapes to solve problems as they participate in hands-on activities.
Curated OER
Problem Solving Using Power Polygons
Students investigate geometric shapes by creating figures on a plane. In this polygon lesson, students complete a worksheet based on the angles in a power polygon. Students identify the different types of polygons and define their...
Curated OER
Dream Bedroom Floor Plan
Students build and apply concepts of geometry. In this geometry lesson, students create a building using proportions and scale drawings. They use Cabri technology to create a virtual drawing first.
Curated OER
Dream Bedroom Floor Plan
Young scholars construct using Cabri software. In this geometry instructional activity, students convert between units and apply the correct measurements to build objects. They create the room virtually and manipulate the shapes to the...
Curated OER
Identifying Angles
Fourth graders examine the various characteristics of angles. In groups, they identify angles in the real world and which angles are used for buildings. To end the instructional activity, they use their bodies to represent the...