Fourth and fifth graders investigate angles and name them according to the criteria for obtuse, acute, and right angles. They examine a human-made yarn pattern on the floor of their classroom and identify angles, vertices, and types of...

Once you start looking, angles appear everywhere in our daily lives. A creative lesson has learners use the angles created by a fuel gauge to practice the Angle Addition Postulate. They see how changing the angle parts does not...

Fourth and fifth graders make a protractor and identify various angle types. In this protractor and angle lesson, learners make their own protractor and use it to measure a variety of angles. They complete worksheets while identifying...

Identify triangles by their angle measures and side lengths by looking at and measuring angle measures and side lengths. Use Cabri Jr. to construct various triangles, then manipulate the construction to create the 6 types of triangles,...

Students measure angles using a plane table kit. In this geometry lesson, students use trigonometric identities to find the values of the length of a football field.

Build angles from angles. Using the Angle Addition Postulate, learners find the measures of unknown angles. The interactive simulation shows a visual representation of the postulate and allows individuals to manipulate the angles and...

Learners identify and create angles. In this angle measurement lesson, students use sticks to make models of angles, then measure and name each angle.

Learners estimate angle measures in this this estimating angle measures instructional activity. They use an application on their graphing calculator that shows various settings involving angles and then they estimate the angle measure of...

Middle schoolers explore angle measure as they estimate angle measure and measure and draw angles of less than 360 degrees. The lesson emphasizes the use of estimation when measuring angles.

Inscribed angles are central to the lesson. Young mathematicians build upon concepts learned in the previous lesson and formalize the Inscribed Angle Theorem relating inscribed and central angles. The lesson then guides learners to prove...

Student complete worksheet using the definitions of lines and angle vocabulary. They define the word and follow a direction given on the worksheet such "construct a line." They complete an online tutorial on how to measure angles using a...

High schoolers explore quadrilaterals in this geometry lesson. They will draw a quadrilateral, measure the angles, and find the sum of the measures of the interior angles using Cabri Jr. The interactive capabilities of Cabri Jr. allow...

Angles and triangles: they're all connected. Uncover the connections between angles in triangles. Scholars learn how to find both exterior and interior angle measures in triangles. The lesson emphasizes the vocabulary related to these...

Prove the Angle Sum Theorem of a triangle using parallel line and transversal angle relationships. Pupils create a triangle from parallel lines and transversals. They find angle measures to show that the angles of a triangle must total...

This a fun problem for young geometers to play with while gaining important insight into deductive reasoning. Some will find the answers very quickly, others might take a less direct path, but all will use their knowledge of the sum of...

Students investigate geometric relationship using conjecture about linear pairs and vertical angles. In this geometry lesson, students apply their theorems and previous geometry knowledge to solve for and find angles of linear...

Acute or obtuse? Seems right to me! As scholars explore the simulation, they investigate angle measures. Questions ask them to classify the angles using correct naming conventions.

Students use principles of geometry to measure the circumference of the Earth. In this applied geometry lesson, students use mathematics to determine scientific information. They make measurements, calculate the central angle, and...

Is that a right triangle or a wrong triangle? Young mathematicians look at eleven different shapes and use a measuring tool of their choice to determine which triangles have right angles. Consider cutting out sets of the shapes to...

Explore angle relationships created by parallel lines and transversals. The 13th lesson of 18 prompts scholars use transparency paper to discover angle relationships related to transversals. Learners find out that these angles pairs are...

How can learners use algebra to solve a geometry problem? Help learners create an equation that shows the relationship between the number of sides of a polygon and the sum of the interior angles. Students are asked to divide the...

It's all about the patterns! Young scholars learn that the unit circle repeats itself in all four quadrants. Using these patterns, they evaluate the sine, cosine, and tangent of special angles.

High schoolers investigate the sum of the measures of the angles of a triangle. They draw a triangle and measure the interior angles. Using Cabri Jr., learners find the sum of the measures of the interior angles. The instructional...

Building trigonometric basics here will last a mathematical lifetime. Learners expand on the previous lesson in a 36-part series by examining relationships between the sine and cosine of complementary angles. They also review the...