Curated OER
Varieties of Quadrilaterals
Young scholars classify quadrilaterals, In this quadrilaterals activity, students watch a video about parallelograms, discuss the different types of quadrilaterals, and complete a worksheet classifying quadrilaterals.
Curated OER
Exploring Polygons and The Greedy Triangle
Excellent lesson plan! Anne Linehane's geometry story, The Greedy Triangle, offers an opportunity to practice forming various types of polygons with your learners. Using elastic bands (or Chinese jump ropes),...
Illustrative Mathematics
Right Triangles Inscribed in Circles II
So many times the characteristics of triangles are presented as a vocabulary-type of activity, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...
Everyday Mathematics
Mathematics Within: Slope and Triangles
Learners discover a method for determining the slope of a line by creating and comparing similar triangles. They fold coordinate grids to make three similar triangles then measure the sides to compare the relationships between the...
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....
Curated OER
Angles Activities
A series of geometry worksheets have mathematicians constructing, dissecting, overlapping, and measuring as they analyze angles in various contexts. Learners use symmetry and reflections in a compass rose to write instructions on...
Curated OER
Area of Quadrilaterals
In this area of quadrilaterals worksheet, 10th graders solve and complete 5 various types of problems. First, they solve each of the triangles shown and find the area of each triangle. Then, students prove that the sum of the squares of...
Virginia Department of Education
Exploring Quadrilaterals
Sort this resource into the Use pile. Scholars investigate attributes of quadrilaterals and then use the results to sort and classify the shapes labeling each figure with their properties to justify the classifications.
Curated OER
Identify Geometric Shapes
Practice identifying quadrilaterals, triangles, and closed curves with this worksheet. Given a series of shapes, learners check boxes next to each shape to indicate whether it under the correct label. Possible shape types are...
Curated OER
Triangles
Students identify triangles in the real world and construct their own triangle using drinking straws. They explore abstract triangles and find additional geometric shapes such as trapezoids. Students discuss similar shapes and examine...
Curated OER
Special Triangles and Quadrilaterals
In this special triangles learning exercise, students examine given special triangles. They determine the length of a missing side and/or the measurement of a missing angle for given triangles and quadrilaterals. Students justify their...
Curated OER
Angles, Triangles, Quadrilaterals, Circles and Related
Students classify angles. In this angles lesson, students explore the characteristics of angles, triangles, quadrilaterals and circles. They identify polygons and sing a classifying angles song. Students participate in a manipulative...
Curated OER
The Quirky Quadrilateral
Fourth graders identify and classify different triangles and quadrilaterals. Then they demonstrate an understanding of plane and solid geometric objects and use this knowledge to show relationships and solve specific problems. Students...
Curated OER
Geometry of Triangles - Week 6
In this triangle worksheet, students explore the characteristics of triangles. They find the area of a pentagon, lengths of the sides of a triangle and the area of a quadrilateral. This two-page worksheet contains seven problems.
Curated OER
Isosceles Right Triangle
In this isosceles right triangle worksheet, 10th graders solve and complete 5 different constructions of composition and decomposition. First, they make 4 congruent isosceles triangles with the model on the left. Then, students create...
Curated OER
Area of Triangle
In this area worksheet, students read and problem solve the area of 8 triangles. Students show their work on each problem on the worksheet.
Curated OER
Investigation - Square Numbers and Triangle Numbers
Fifth graders investigate growth patterns using blocks. In this square and triangle numbers instructional activity, 5th graders predict sizes of larger triangles and squares based on numerical patterns they observed while building.
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.
Curated OER
Section 2.5 - Problem Solving (Part B)
Trying to figure out the perimeter of a geometric figure? Here are a few word problems to set up algebraic equations to solve for perimeter. There are also some word problems to set up algebraic equations to solve for angles in a...
Mathematics Vision Project
Congruence, Construction and Proof
Learn about constructing figures, proofs, and transformations. The seventh unit in a course of nine makes the connections between geometric constructions, congruence, and proofs. Scholars learn to construct special quadrilaterals,...
Curated OER
Squares, Rectangles, and Right Triangles
Youngsters identify and draw polygons including squares, rectangles, and right triangles. In this polygons lesson plan, everyone draws these shapes that have right angles in their math journals.
Helping with Math
Geometry: Areas of Triangles
For this areas of triangles instructional activity, students observe given polygons. They determine the area of triangles, rectangles and compound figures. This one-page instructional activity contains 5 multi-step problems. This...
Curated OER
Sea Squares
In this sea squares worksheet, 10th graders solve 5 different problems that include various geometrical figures. First, they draw a number line using one color. Then, students draw 2 obtuse angles and 3 isosceles triangles with different...
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.