Illustrative Mathematics
Tangent to a Circle From a Point
Learners see application of construction techniques in a short but sophisticated problem. Combining the properties of inscribed triangles with tangent lines and radii makes a nice bridge between units, a way of using information about...
Curated OER
Trig Cheat Sheet
Your pre-calculus learners will make use of this wonderful cheat sheet that summarizes all things trigonometric. Definitions based on both the unit circle and the right triangle are included, as well as many convenient trigonometric...
Texas Instruments
Drawing a Line Tangent to a Circle
Explore lines tangent to a circle. In this math lesson, students manipulate circles and lines on a TI calculator. They draw a circle and analyze perpendicular lines intersecting the circle in only one place. This activity works best if...
Curated OER
Area of Circles and Probability
Students investigate the area of squares and circles. For this geometry lesson, students calculate the area and probability of simple events. They work on a laptop using Safari.
101 Questions
Suitcase Circle
Analyze patterns in a circular arrangement. After using a geometric construction to complete a circle, learners use proportional reasoning to make predictions. By determining the length of an arc built from suitcases, they estimate the...
CK-12 Foundation
Circles Centered at the Origin: The Map of the Beta Solar System
Calculate galactic orbits in a far-out resource. Pupils drag a point on a circle to graph the orbit of a fictional planet. Using the equation, they find points through which the orbit passes. To finish the simulation, users determine the...
EngageNY
Awkward! Who Chose the Number 360, Anyway?
Don't give your classes the third degree. Use radians instead! While working with degrees, learners find that they are not efficient and explore radians as an alternative. They convert between the two measures and use radians with the...
Curated OER
Math Handbook: Trigonometry
You'll be spinning in unit circles once you read through this jumbo-sized resource of everything you need to know about trigonometry. Each page has color-coded examples with explicit directions that detail the problems and formulas.
Curated OER
The Unit Circle
Students solve problems using the unit circle. In this precalculus lesson, students identify angles using the properties of the unit circle. They observe the trigonometric graphs and sine, cosine and tangent.
Curated OER
Unit Circle and Triangle
Students apply the Unit Circle to solve ratios of triangles. In this geometry lesson, students derive the different ratios of a triangle using the Pythagorean Theorem. They find the angles of a unit circle using a right triangle.
Curated OER
Unit Circle
Students investigate the different properties of a unit circle. For this geometry lesson, students identify the six different values of trigonometric functions. They solve trigonometric equations using values derived from the unit circle.
Curated OER
Right Triangles and Unit Circles
Students evaluate the six trigonometric values of a trig function. In this trigonometry lesson, students use the Unit Circle to find the values of right triangles and their angles. They identify an angle of elevation and depression.
Curated OER
The Radian Walk
Students play a game to learn angle measures in radians. In this precalculus/trigonometry activity, students play a game similar to a cake walk. When the music stops, which ever student is selected, names his/her coordinates and place on...
Mathematics Assessment Project
Solving Problems with Circles and Triangles
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Mathematics Assessment Project
Sorting Equations of Circles 1
Round and round we go. Learners first complete a task on writing equations of circles. They then take part in a collaborative activity categorizing a set of equations for circles based on the radius and center.
Curated OER
The Unit Circle
Students relate the trigonometric functions to the coordinates of the unit circle with access to explorelearning.com. They determine the signs of trigonometric functions in each quadrant.
Curated OER
Review 13.1-13.2: Unit Circle
In this unit circle worksheet, students find the sine, cosine, tangent, cotangent, and co-secant of given values. They determine the exact value of trigonometric ratios. Students convert from degrees to radians. This two-page worksheet...
Mathematics Vision Project
Module 6: Trigonometric Functions
Create trigonometric functions from circles. The first lesson of the module begins by finding coordinates along a circular path created by a Ferris Wheel. As the lessons progress, pupils graph trigonometric functions and relate them to...
EngageNY
Mid-Module Assessment Task: Pre-Calculus Module 4
Challenge scholars to show what they know about properties and addition and subtraction formulas for trigonometric functions. The resource provides a mid-unit check on the progress toward mastery of trigonometric concepts. The areas...
Illustrative Mathematics
Similar Circles
Young geometers flex their transformation muscles in this brief but powerful exercise using dilations and translations to develop the similarity of circles. The plan provides guidelines to help learners navigate a pair of deceptively...
Curated OER
Unit Circle Lesson Plan
Learners identify different locations on a unit circle. In this precalculus lesson, students identify the different trig properties and rewrite the equation of a circle in standard form. They use mnemonic devices to help them remember...
Inside Mathematics
Circles in Triangles
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
PHET
Trig Tour
Unit circles and trigonometric graphs go hand in hand. Pupils see how traversing the unit circle allows for the creation of graphs for trigonometric functions. They also see trigonometric ratios in terms of the ordered pairs of points on...
CK-12 Foundation
Conversion between Degrees and Radians: Arc and Radians Relationship
How are arc lengths and radians related? An interactive resource demonstrates the relationship as pupils create arc lengths in a unit circle and compare them to the angle measurements. Questions ask individuals to build upon this...