Buffalo State
A Five Day Approach to Using Technology and Manipulatives to Explore Area and Perimeter
Young mathematicians build an understanding of area and perimeter with their own two hands in a series of interactive geometry lessons. Through the use of different math manipulatives, children investigate the properties of rectangles,...
One Billion
Math, Age 3-5
Jump start children's math education with this fun basic skills resource. Offering dozens of different touch-and-swipe activities with colorful graphics, this program is perfect for all young learners.
Illustrative Mathematics
Similar Triangles
Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...
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 Triangle,...
Alabama Learning Exchange
Triangle Area: No Height? Use the Sine
No height? No problem! Learners use their knowledge and a little help from GeoGebra to develop the Law of Sines formula. The Law of Sines helps to determine the height of triangles to calculate the area.
CPALMS
2D Rotations of Triangles
Where does the line of rotation need to be to get a cone? Pupils respond to three questions involving rotating a right triangle about different lines. The scholars describe the solid created along with providing details about its...
Curriculum Corner
8th Grade Math Common Core Checklist
Ensure your eighth graders get the most out of their math education with this series of Common Core checklists. Rewriting each standard as an "I can" statement, this resource helps teachers keep a record of when each standard was taught,...
Curated OER
Exploring Centers of a Triangle: Part 2
Students model and solve a real-world problem by constructing the centroid of a triangle. They explore relationships of the medians of a triangle and investigate how the centroid partitions each of the medians. Students investigate...
Curated OER
Triangle Inequality Theorems Investigation
Students estimate and measure triangles. In this geometry lesson, students identify the relationship between three sides and a triangle. They use the inequality theorem to decide if a triangle will be formed or not.
Curated OER
Alice in Fractalland
Take your class on a field trip to Fractalland where they'll learn all about number and shape patterns. Based on Disney's movie Alice in Wonderland, this resource takes young mathematicians on an adventure as they explore patterns in...
Curated OER
30-60-90 Right Triangles in Cabri Jr.
Young mathematicians draw and label right triangles using Cabri Jr. technology. They create other special right triangles and identify the length of the hypotenuse and each leg. Students explore the ratios to determine how the hypotenuse...
Curriculum Corner
8th Grade Math "I Can" Statement Posters
Clarify the Common Core standards for your eighth grade mathematicians with this series of classroom displays. By rewriting each standard as an achievable "I can" statement, these posters give students clear goals to work toward...
EngageNY
Modeling Riverbeds with Polynomials (part 2)
Examine the power of technology while modeling with polynomial functions. Using the website wolfram alpha, learners develop a polynomial function to model the shape of a riverbed. Ultimately, they determine the flow rate through the river.
Curated OER
Exploring Characteristics of Triangles
Young scholars draw triangles and explore the classification of each using the measures of interior angles and lengths of sides. They investigate the sum of the interior angles of various triangles and conjecture and prove the theorem:...
Radford University
Triangular Irrigation
Try to keep the pipe short. Learners investigate where to place a water pump to use the least amount of pipe. Scholars use their knowledge of reflections and congruent triangles to find the best location for the water pump. Finally, they...
Curated OER
Triangles & Congruence, Proportions & Similarity, Right Triangle & Trigonometry
Students are introduced to the topic of congruence and proportions in Geometry. Using technology, they construct and validate the properties of various geometric figures and identify whether it is congruent or proportion to the objects...
Noyce Foundation
Parallelogram
Parallelograms are pairs of triangles all the way around. Pupils measure to determine the area and perimeter of a parallelogram. They then find the area of the tirangles formed by drawing a diagonal of the parallelogram and compare their...
Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Inside Mathematics
Rhombuses
Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...
Curated OER
What are the Kinds of Triangles?
Fifth graders classify triangles. In this triangle lesson, 5th graders learn about the characteristics that make up a triangle. They are instructed through video, PowerPoint slides, and teacher-led demonstrations.
Curated OER
Triangle Inequality Theorem
High schoolers investigate the relationship between angle measures and sides of a triangle and the relationships among the three sides of a triangle. The use of technology (Cabri, Jr.) allows learners to make and test conjectures as they...
Curated OER
How many isosceles triangles can you find?
Seventh graders recognize the characteristics of isosceles triangles. In this isosceles triangle lesson, 7th graders use geoboards to create isosceles triangles. Students record results and explain why they have an isosceles triangle.
Curated OER
Exploring Geometric Figures
Tenth graders explore mathematics by participating in hands-on daily activities. Learners identify a list of different shapes and classify them by shape, size, sides and vertices. They utilize tangrams and geometric pieces to gain an...
Curated OER
Similar and Congruent Triangles
Students create and classify different types of triangles using an online geo-board. They explore the concepts of similar and congruent as they discover how to draw similar and congruent triangles.