CK-12 Foundation
Identify Accurate Drawings of Triangles: Law of Cosines
Drawing triangles is easy, even if you have to calculate the exact length of its sides. Scholars use the Law of Cosines to find missing sides of triangles. An interactive helps them check their answers.
Mathematics Assessment Project
Hopewell Geometry
Right triangles from 2,000 years ago? Learners investigate different right triangles found in the earthworks of the Hopewell people, a Native American culture that populated the United States from 200BC to AD 500. Learners apply concepts...
Mathematics Assessment Project
Triangular Frameworks
What did the triangle say to the circle? You're pointless! Class members will get the point when they investigate relationships between side lengths of a triangle using the Triangle Inequality Theorem. Pupils then create an algebraic...
School Mathematics Project
Resource Sheets
This extensive and far-reaching collection of worksheets puts a new twist on many basic concepts. Learners use multiplication to trace a path from one point to another, tile a plane by converting between improper and proper fractions,...
Curated OER
Triangles Inscribed in a Circle
Are you tired of answers without understanding? Learners can give a correct response, but do they really understand the concept? Have young mathematicians think deeper about linear functions, angles, and formulas in algebra. Learners are...
Illustrative Mathematics
Applying the Pythagorean Theorem in a Mathematical Context
Participants who use this resource will apply the Pythagorean Theorem to show whether or not the shaded triangle inscribed in a rectangle is a right triangle. Once all of the sides on the shaded triangle are found, it is important that...
Exploratorium
The Four-Square Quilt
Youngsters recognize that triangles can be combined together to make various shapes. The learning activity provides a series of seven steps that engage children in applying transformations to triangles. Pupils use a quilt template and...
Curated OER
What's in a Shape?
Students explore characteristics of shapes by making and using tangram sets. They discover how the tangram pieces are related to one another, and determine how many different combinations of the triangles, squares, and parallelograms in...
Curated OER
Math Mediator Lesson 10: Slope
Students explore the concept of slope. In this Algebra I instructional activity, students investigate the definition of slope as rise over run or change in y compared to change in x. The instructional activity includes a real-world...
Curated OER
Discover the Pythagorean Theorem
Middle schoolers explore the Pythagoras theorem. In this geometry lesson, students make right triangles and identify the parts of the triangle. Middle schoolers complete measurements of the sides of the triangle.
Curated OER
Circles, Squares, Triangles and Rectangles In Our World
Here is an engaging geometry instructional activity which has students identify the properties of shapes and cut shapes out of magazines. They make cookies using cookie cutters in various shapes.
Curated OER
Flying with Pythagoras
A lengthy narrative about Pythagoras and his students precedes an activity in which your young mathematicians practice using the Pythagorean theorem to solve three problems about flight and distance. Answers are provided.
Curated OER
Exploring Triangles
Learners research the different types of triangles, including right, isosceles, scalene, and equilateral triangles. They identify the characteristics of various types of triangles and then draw them using appropriate vocabulary to...
Curated OER
Perimeter & Area Worksheet I
In this perimeter and area worksheet, students 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
Perimeter and Area Worksheet II
In this perimeter and area worksheet, students find the perimeter and area of polygons. They use the proper formula to find the perimeter and area of circles, parallelograms, triangles, and rectangles. Students complete solve ten problems.
Curated OER
Applying the Pythagorean Theorem
Learners use the Pythagorean Theorem to find the distances between two points. Use this Pythagorean Theorem lesson plan to have learners find the distances on a coordinate plane in small groups.
Curated OER
Pythagorean Theorem
For this measurement lesson, learners examine the Pythagorean Theorem, perimeter, and areas of right triangles. They record their measurements and research their findings on a grid.
Curated OER
The Pythagorean Theorem Lesson 2
Learners discuss and review examples of the Pythagorean Theorem using a GSP, Geometer's Sketchpad, activity.
Centre for Education in Mathematics and Computing
Roots and the Pythagorean Theorem
In this roots and the Pythagorean Theorem worksheet, learners solve 15 different types of problems related to square roots and applying the Pythagorean Theorem. They first determine the square root of each number and then, the cube root....
Curated OER
Central Valley Math Project
Middle schoolers study the Pythagorean Theorem. They describe what it means to square a number. Pupilsuse the Pythagorean Theorem to prove the sides of given triangles, and use geometric pieces of paper to create a right triangle and...
Curated OER
Six Exercise Sets on Transformations
Middle and high schoolers solve fifteen problems from six exercise sets covering transformations, reflections, rotations, and enlargements. The solutions are provided.
Curated OER
Understand Categories of Shapes
This colorful set of shapes and figures is the data set learners need to fill out an extensive table. For each of 11 types of shapes or figures they record the quantity and how many corners and sides each has. This becomes more difficult...
Curated OER
Understanding Categories of Shapes
What are these shapes? Scholars match seven shapes to their names: rhombus, sphere, square, cone, circle, triangle, and parallelogram. Although there isn't much to this worksheet, the shapes are nicely colored and it would make a good...
Curated OER
Recognize and Draw Shapes
What type of shape is this? Learners practice identifying shape attributes as they name a parallelogram and an oval and count the sides of a cube and a triangle. There are multiple-choice answers for the shape-name questions, so...