National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy...
Digging Into Math
Classifying Triangles
Young mathematicians explore the world of three-sided shapes in this instructional activity on the different types of triangles. Starting with a general introduction to classification using Venn diagrams, children learn how to...
CK-12 Foundation
Special Triangle Ratios: Special Right Triangle Ratios
Go from one side length to any other side length with special right triangles. Individuals use the interactive to investigate the ratio of sides in 45-45 and 30-60 right triangles. Scholars make generalizations about the types of special...
Mathematics Vision Project
Geometric Figures
Logical thinking is at the forefront of this jam-packed lesson, with young mathematicians not only investigating geometric concepts but also how they "know what they know". Through each activity and worksheet, learners wrestle with...
Charleston School District
Parallel Lines Cut by a Transversal
Pupils study angle measurements between different types of angles associated with parallel lines and transversals. The independent practice asks pupils to identify the types of angles in a diagram and to determine the measure of...
EngageNY
Putting the Law of Cosines and the Law of Sines to Use
Use the Law of Cosines and the Law of Sines to solve problems using the sums of vectors. Pupils work on several different types of real-world problems that can be modeled using triangles with three known measurements. In the process,...
Mathematics Vision Project
Similarity and Right Triangle Trigonometry
Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...
Cornell University
Bridge Building
Bridge the gaps in your knowledge of bridges. Individuals learn about bridge types by building models. The activity introduces beam bridges, arch bridges, truss bridges, and suspension bridges.
Willow Tree
Common Geometric Figures
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons.
Mathed Up!
Reflections
Tracing paper is not just for art anymore — pupils can use it to find reflected images, too! Two videos show how to reflect images using tracing paper and find the reflection between the pre-image and image. Learners perform reflections...
Illustrative Mathematics
Introduction to Linear Functions
Introduce your algebra learners to linear and quadratic functions. Learners compare the differences and relate them back to the equations and graphs. Lead your class to discussions on the properties of a function or a constant slope...
Curated OER
Know Your Polygons!
Students identify and categorize different polygons. In this polygons lesson plan, students research and identify properties of polygons, identify different polygon shapes, and categorize different triangles and quadrilaterals.
CCSS Math Activities
Smarter Balanced Sample Items: High School Math – Claim 2
Problem solve across the content standards. The presentation slides provide 19 sample items from the Smarter Balanced high school assessment. Items illustrate Claim 2, problem solving, of the test and are drawn from all the high school...