Illustrative Mathematics
Coins in a Circular Pattern
What starts as a basic question of division and remainders quickly turns abstract in this question of related ratios and radii. The class works to surround a central coin with coins of the same and different values, then develops a...
Illustrative Mathematics
Two Wheels and a Belt
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
Pearson
Performance Based Assessment Practice Test (Geometry)
The incredibly broad topic base of a geometry class makes full-length practice tests like this one, especially ones that include a number of open response questions, invaluable.  Here the class can really get that hands-on experience...
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...
Curated OER
Finding the Area of an Equilateral Triangle
The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...
National Research Center for Career and Technical Education
Manufacturing: Gas Metal Arc Welding (GMAW) Shielding Gas Mix
Middle schoolers apply math to the real-world skill of choosing the correct shielding gas mixture for welding. Even if you do not have shielding gas cylinders on hand for demonstrating, the concepts of converting percentages into...
National Research Center for Career and Technical Education
Architecture and Construction: Stair Construction
Within the context of the construction industry, algebra pros begin to calculate slope from the sizes of stair steps. This is a terrific lesson, especially for aspiring engineers. Just be aware that it might be a stretch to meet all of...
Curated OER
Fish Tale
Here is a cute problem that requires visualizing two-dimensional shapes within a three-dimensional object, and using properties of triangles and the Pythagorean theorem to solve a real-world problem. There is a small mistake in this...
Curated OER
Special Right Triangles
Using the Pythagorean Theorem to solve for missing angles, students evaluate right triangles and their properties.
Curated OER
The Pythagorean Theorem and Classifying Triangles
Through the examination of the relationship between the lengths of the sides of a triangles students will learn the classification of triangles (acute, right, or obtuse).
Curated OER
Number Sense: Real Numbers
Using a scientific calculator and an 11-page guide sheet, middle schoolers investigate real numbers and problem-solving properties. The publisher links this resource to Common Core standard for seventh grade math, but you may find it a...
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...
Curated OER
Pythagorean Relationships
Oh that Pythagorean Theorem is so useful. Learners engage in a 45 minute learning activity that requires them to solve for missing angles and sides of a right triangle. They'll use the Pythagorean Theorem to find the rations of sides and...
Curated OER
Equation of a Circle
Students write the equation of a circle. In this geometry lesson, students check the solution of a coordinate pair by evaluating them. They graph the circle given the equation and radius.
Curated OER
Area Measures and Right Triangles
Your class will investigate the relationship among different triangles. This geometry lesson, demonstrates how to make a connection between triangles and the Pythagorean Theorem. They identify the missing side or angle of a triangle.
Curated OER
Altitude to the Hypotenuse
Can your class solve right triangles and identify the properties common to right triangles? They will investigate and state the relationship between the altitude to the hypotenuse and the two segments of the hypotenuse formed by the...
Curated OER
Trigonometry Ratios
Students identify the different angles and sides of a triangle. In this geometry activity, students identify the six trigonometric ratios. They graph the graph of each trig function and analyze it.
Curated OER
Pythagorean Triples
Teach how to solve problems with right triangles. Students use the Pythagorean Theorem to identify missing sides and angles. Then, they will define and use the Pythagorean Triples to solve problems.
Curated OER
Gateway Arc Length
Learners differentiate and calculate the length of an arc. They define an arc and relate it to the area of a circle and integrate the function to solve the equations. Students use their TI calculators to graph the equation.
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. High schoolers explore the ratios to determine how the...
Curated OER
Trigonometric Ratios
Learners investigate properties of the unit circle using sine, cosine and tangent. They analyze the answers to questions about the unit circle based on a right triangle.
Texas Instruments
The Leaning Tower of Pisa
Learners estimate the equation of a line, angle of elevation and depression in this math lesson. They analyze e famous landmark design and make connections to algebra and geometry. They will also generate an equation, model the x and y...
Texas Instruments
What's the Trig?
Learners determine the trigonometric relationships within a triangle as they construct a right triangle on the Ti-89. They find the sine, cosine, and tangent of various angles of their triangle construction.
Curated OER
Hunter Fred's Quest for Dinner
Learners solve problems using trigonometric functions, specifically a problem about a tree stand. Pupils try to maximize the distance of hunting sight given certain restrictions. They use the Pythagorean Theorem, sine, cosine, and...