CK-12 Foundation
Pythagorean Theorem to Determine Distance: Ladders
Young mathematicians to the rescue! Pupils use an interactive to find lengths relating a ladder against a building. The problems involve determining how long a ladder must be to reach a given floor to what floor can a given ladder reach.
Utah Education Network (UEN)
Finding Slope of a Line from Graphs, Tables, and Ordered Pairs
Middle schoolers explore the concept of slope in numerous ways and start to look at simple linear equations. They describe the slope in a variety of ways such as the steepness of a line, developing a ratio, using graphs, using similar...
Curated OER
Studying Special Segments in Triangles
Learners investigate special segments in triangles. In this geometry instructional activity, students graph, compare, estimate and predict findings based on their data. They differentiate between similarity and congruence of triangles.
Curated OER
Math: Investigating Triangles
Tenth graders identify the trigonometric ratios for right angled triangles. Through independent investigation, they discover the constancy between the ratios of any two sides of similar triangles. In an alternative method, 10th graders...
Mathematics Assessment Project
College and Career Readiness Mathematics Test B1
Math was easier before it got mixed up with the alphabet. A 10-page test covers material from multiple years of high school math. Scholars demonstrate knowledge across domains with a mixture of short answer and applied problems.
Curated OER
The Hand of Chandra!
In this nebula activity, students read about the Chandra X-ray Observatory that captured the given image of a pulsar and its nebula. Students solve 3 problems including using similar triangles and proportions to find the image width,...
West Contra Costa Unified School District
Introduction to Trigonometric Functions
Scholars first learn the definitions of the sine ratio, the cosine ratio, and the tangent ratio. After mastering these definitions, they use the new information to solve triangles.
Curated OER
T Points from Directions
Here is a lesson that starts with having geometers translate points using compass directions into an accurate picture of the problem. Then they must use their knowledge of the Pythagorean theorem or similar triangles to solve. This makes...
CK-12 Foundation
Identifying Sets of Pythagorean Triples: The iPad is a Pythagorean Triple
Compare iPad and HDTV aspect ratios. Individuals use the interactive to determine whether the measurements of screens represent a Pythagorean triple. The pupils determine what changes are needed to make a Pythagorean triple.
Curated OER
Amazing Consistent Ratios
Students derive the six trigonometric identities. In this trigonometry lesson, students find the ratios of sine, cosine and tangent using the right triangle. They use properties of the Pythagorean Theorem to find the trig identities.
Curated OER
Exploring Altitudes in Math
Students draw and calculate altitudes. They draw the altitude of acute, right and obtuse triangles and calculate the altitude of a triangle using the Pythagorean theorem.
Curated OER
Proofs of the Pythagorean Theorem
Working individually and collaboratively, geometers gain a clear understanding of the Pythagorean theorem. They create, explain, and compare proofs of the theorem. Proofs involve areas of trapezoids, squares, and triangles, congruent...
EngageNY
Law of Cosines
Build upon the Pythagorean Theorem with the Law of Cosines. The 10th part of a 16-part series introduces the Law of Cosines. Class members use the the geometric representation of the Pythagorean Theorem to develop a proof of the Law of...
EngageNY
Definition and Properties of Volume
Lead a discussion on the similarities between the properties of area and the properties of volume. Using upper and lower approximations, pupils arrive at the formula for the volume of a general cylinder.
Curated OER
Proportional Segments Between Parallel Lines
Students identify similar triangles. In this proportional segments lesson, students identify corresponding sides, set up ratios, and find the length of the missing side of a triangle. They use the parallel/proportionality conjecture to...
Alabama Learning Exchange
Trapezoids: What's Equal or Right About Them?
Pupils explore the concept of trapezoids. In this trapezoids instructional activity, students identify legs and bases of a trapezoid. Pupils discuss the similarities and differences between isosceles trapezoids and right trapezoids. ...
Curated OER
ndirect Measurement Technique: Using Trigonometric Ratios
Ninth graders find the height of an object that would be difficult or impossible to measure directly. They construct and use a Clinometer to measure the angle of elevation (or depression). Students create a sketch of the measurement...
Curated OER
Trigonometry Ratios
Learners identify the different angles and sides of a triangle. In this geometry lesson, students identify the six trigonometric ratios. They graph the graph of each trig function and analyze it.
Curated OER
Side Splitter Triangles
Students investigate the side splitter theorem. In this geometry lesson plan, students estimate and solve problems dealing with ratios and proportions. They identify angles created by lines that are parallel.
Mathematics Assessment Project
Modeling Motion: Rolling Cups
Connect the size of a rolling cup to the size of circle it makes. Pupils view videos of cups of different sizes rolling in a circle. Using the videos and additional data, they attempt to determine a relationship between cup measurements...
Curated OER
Transformations and Congruence
In this transformations and congruence learning exercise, 10th graders solve and complete 5 different types of problems. First, they calculate the length of a line giving their answer in 3 significant figures. Then, students prove that...
Curated OER
Scale Factor Area Perimeter
Mathematicians compare triangles at different scales. In this geometry lesson, students calculate the area and perimeter of triangles. They use the Ti to make observation of the change that takes place as the triangles are dilated.
Curated OER
Archeologist Frieze Patterns
Learners construct frieze patterns using translations and rotations. They will discuss how frieze patterns are similar to jigsaw puzzles and use Cabri Jr. to build a triangle frieze pattern using rotations, translations, and reflections.
Curated OER
Origami Frogs
Ninth graders explore a variety of geometry and science concept while making an origami frog. The fold paper into the shape of a frog and conduct measurement activities including frog leaps.