Mathed Up!
Angles in Triangles and Quadrilaterals
This short video show viewers how to connect the sum of the angles in a triangle to other angle measurements. Pupils determine the missing measures for angles involved with triangles and quadrilaterals. Class members then must explain...
Corbett Maths
Construct a 30 Degree Angle
Split it down the middle. Using the tools of geometric construction, the video shows two different methods of constructing a 30-degree angle. The first method bisects an angle of an equilateral triangle. The second uses the diagonal of a...
Corbett Maths
Angle Bisector
Cut it in half with a compass and straightedge! Using construction tools, a video shows how to create an angle bisector. The presenter points out what it means to bisect an angle in terms of the measure and distances from the sides of...
EngageNY
One-Step Problems in the Real World
Mirror, mirror on the wall, which is the fairest resource of them all? Individuals write and solve one-step equations for problems about angle measurement, including those involving mirrors. Both mathematical and real-world problems are...
EngageNY
Secant Angle Theorem, Exterior Case
It doesn't matter whether secant lines intersect inside or outside the circle, right? Scholars extend concepts from the previous lesson to investigate angles created by secant lines that intersect at a point exterior to the circle....
K6 Math
Complementary and Supplementary Angles #1
Learners are given one angle measure, and then determine the corresponding supplementary or complementary angle. A reference web site is given for additional activities. This assignement can be adapted to demonstrate that angle measure...
Curated OER
Measuring Angles
In this measuring angles worksheet, students measure a set of 5 angles, checking a set of features that apply to each. A reference web site is given for additional activities.
Curated OER
Geometry - Angles Overview
Learners address 14 questions that include naming all pairs of opposite and supplementary angles for sets of intersecting lines and then, finding the measure of the unknown angle. They determine the measure of the angle that is...
Charleston School District
Parallel Lines Cut by a Transversal
Pupils study angle measurements between different types of angles associated with parallel lines and transversals. The independent practice asks pupils to identify the types of angles in a diagram and to determine the measure of angles.
Kuta Software
Polygons and Angles
Get out those protractors! Geometers measure interior and exterior angles of 10 polygons, including a 24-gon. They also calculate the interior angle sum of the polygons.
Curated OER
Angle Relationships
Over the course of 18 problems, learners identify angles as complementary, supplementary, vertical or adjacent. They name relationships in angles such as alternate interior, corresponding, and alternate exterior angles. They apply the...
Curated OER
Angle Measures
In this angles instructional activity, students solve 20 problems pertaining to angle measurement and classification. This page is intended to be an online activity, but can be completed on paper.
Curated OER
Measure Angles: Greater Less Than or Equal To?
In this measuring angles instructional activity, students determine whether given angles or more than, less than or equal to 90 degrees. 
Willow Tree
Interior Angles, Exterior Angles, and Diagonals of Polygons
How does the number of sides of a polygon affect the angle measures? Learners recognize a pattern in finding the total measure of interior and exterior angles and the number of diagonals. They use the patterns to calculate the number of...
Curated OER
Drawing Angles
Get out those protractors! Once geometers can identify obtuse, acute, right, and straight angles, get them to measure and draw their own. There are six boxes here, each with an angle measurement. Learners use a protractor to draw the...
Willow Tree
Angle Sum Property of Triangles
All triangles have some things in common. Using these properties of triangles, learners find missing angle measures. Scholars use the Angle Sum Property and properties of special triangles throughout the lesson.
EngageNY
The Inscribed Angle Alternate – A Tangent Angle
You know the Inscribed Angle Theorem and you know about tangent lines; now let's consider them together! Learners first explore angle measures when one of the rays of the angle is a tangent to a circle. They then apply their newfound...
Curated OER
Estimate then Measure the Angle #1
Practice angle estimation with a worksheet. First learners estimate three angles within 15 degrees, then they measure and name each angle. A reference website is given for additional activities.
Curated OER
Angles (Various)
In this angles instructional activity, students analyze a group of 8 angles. There are no directions for use, but students could measure these with a protractor or classify them as acute, right or obtuse.
Kuta Software
Classifying Angles
Learners sharpen their classification of angles skill with a simple angles worksheet that starts with unlabeled angles and ends with specific angle measures to classify.
Big Kid Science
Measuring Shadows Using an Ancient Method
How did ancient peoples determine the height of really tall objects? Young scientists and mathematicians explore the concept of using shadows to measure height in a hands-on experiment. Paired pupils measure shadows, then calculate the...
Corbett Maths
Angles in the Same Segment – Proof
If angles intercept the same arc, the angles must be the same size. The quick video talks through the proof of showing the reason two inscribed angles that intersect the same arc have the same measurement. Pupils then create their own...
Curated OER
Classify and Measure Angles #2
In this angles activity, students classify and measure 2 given angles. Worksheet is part of a directory, click on line to access worksheets.
Curated OER
Estimating and Measuring Angles (B)
For this estimating and measuring angles review worksheet, students use their math skills to solve 6 problems that require them to estimate and measure each of the 6 angles.