National Council of Teachers of Mathematics
The Math Forum: Famous Problems in the History of Mathematics
On this site, there are several math problems to explore and solve. Look through some solutions by famous mathematicians and expand your thinking about some interesting math concepts. Teachers of elementary grades may want to use this...
Harvard University
University of Harvard: This Is a Stickup!
Students are taught how to make a sundial. The relationship between angles and the sides of a right triangle are explored. Great lesson plan ideas with plenty of background information. The lesson plan is adapted for grade levels k-6...
Purple Math
Purplemath: Basic Triangle Values
This Purplemath lesson explains a simple pictorial way to remember basic reference angle values.
Northeast Parallel Architectures Center, Syracuse University
Npac Reu Program: Graphing With Coordinates in the Plane
This site from the Northeast Parallel Architectures Center, Syracuse University provides a good five-part basic graphing instructor. Covers all the basics clearly. It is divided into links for easier navigation.
Oswego City School District
Regents Exam Prep Center: Pythagorean Theorem
Who was Pythagoras and what is his theorem? Explore this concept and its relationship to the measurement of a right triangle in this test prep lesson plan. The lesson includes an interactive worksheet where learners discover the answers...
Purple Math
Purplemath: Basic Trigonometric Ratios: Examples
Demonstrates how to use trig ratios to do simple solving of triangles.
Physics Aviary
Physics Aviary: Triangle Math
Challenges students figure out ten unknown values for right triangles without getting any problems wrong.
Physics Aviary
Physics Aviary: Triangle Exploration Lab
This lab is designed to have students look at some of the different relationships that exist in a right triangle. Students will be able to change the x-leg and y-leg of the triangle and then measure the angle and the hypotenuse of the...
Khan Academy
Khan Academy: Distance Between Two Points
In this exercise, students practice using the distance formula, which is derived from the Pythagorean Theorem, to find the distance between two points on a coodinate grid. Students receive immediate feedback and have the opportunity to...
Khan Academy
Khan Academy: Use Pythagorean Theorem to Find Right Triangle Side Lengths
Find the length of the hypotenuse or a leg of a right triangle using the Pythagorean Theorem. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Khan Academy
Khan Academy: Use Area of Squares to Visualize Pythagorean Theorem
Apply the Pythagorean theorem and its converse to solve these problems. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Khan Academy
Khan Academy: Use Pythagorean Theorem to Find Isosceles Triangle Side Lengths
Find the missing side lengths of isosceles triangles by using the Pythagorean Theorem. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Khan Academy
Khan Academy: Pythagorean Theorem Challenge
In this exercise, students practice using the Pythagorean Theorem in word problems. Students receive immediate feedback and have the opportunity to watch a video, get hints, or try questions repeatedly.
Math Open Reference
Math Open Reference: Triangles
A complete reference guide to types of triangles and triangle perimeter and area. It provides definitions and interactive animated activities that enhance further explanation.
CK-12 Foundation
Ck 12: Algebra: Pythagorean Theorem and Its Converse
[Free Registration/Login may be required to access all resource tools.] Recognize and use the Pythagorean Theorem
CK-12 Foundation
Ck 12: Algebra: Applications Using the Pythagorean Theorem
[Free Registration/Login may be required to access all resource tools.] In this lesson students use the Pythagorean Theorem to find lengths and distances. Students watch a video tutorial, explore guided notes and attempt practice problems.
Education Place
Houghton Mifflin: Eduplace: What Is It? Pythagorean Theorem
This is a great place for information on the Pythagorean Theorem. Three other sections (tabs at the top) are available, including tips, students' questions, and lesson ideas.
Math Open Reference
Math Open Reference: Sine (Sin) Function Trigonometry
A complete reference guide to the sine function. It provides definitions, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Cuemath
Cuemath: Adjacent
Let's read about the word of adjacent, look at examples, and learn how angles can be adjacent. Check out the interesting examples to know more about this lesson and try your hand at solving a few interactive questions at the end of the...
CK-12 Foundation
Ck 12: Interactive Geometry: 1.7 the Pythagorean Theorem
Explore and discover the Pythagorean theorem.
Math Open Reference
Math Open Reference: Cosine (Cos) Function Trigonometry
A complete reference guide to the cosine function in trigonometry. It provides definitions, examples, and an interactive activity that enhances further explanation.
Khan Academy
Khan Academy: Hypotenuse, Opposite, and Adjacent
In a right triangle, the hypotenuse is the longest side, an 'opposite' side is the one across from a given angle, and an 'adjacent' side is next to a given angle.
Purple Math
Purplemath: The Unit Circle
Relates the unit circle to the method for finding trig ratios in any of the four quadrants. Demonstrates how the unit circle might be useful.
Math2
Math2.org: Trigonometry Functions
A complete look at trig functions. From an "overview," page giving general definitions and important vocab words, to a listing of the 12 trig functions, to an explanation of the three modes used in trigonometry, to the procedures of how...