Curated OER
Properties of Polygons, Parallel Sides, and Right Angles
Have fun with shapes! Third graders read a set of instructions and circle the shape in the description. They work on recognizing parallel sides and right sides. Use this resource as homework after your geometry lesson.
EngageNY
Experiments with Inscribed Angles
Right angles, acute angles, obtuse angles, central angles, inscribed angles: how many types of angles are there? Learners first investigate definitions of inscribed angles, central angles, and intercepted arcs. The majority of the lesson...
Utah Education Network (UEN)
The Angle Tangle
Fourth and fifth graders identify three types of angles, recognize that angles are measured in degrees, measure angles using protractors or angle rulers. They classify angles as a class, classify angles on pattern blocks, and complete a...
Curated OER
Angles - Digger and the Gang
Students explore angle estimation and measurement. In this angle lesson, students define obtuse, acute, and right angles, and practice measuring angles using a protractor. Students participate in an online angle estimation activity.
Curated OER
Angles
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...
AJ Reynolds
Unit 5 Section 2: Measuring Angles
An interactive assignment displays two example angles to teach how to measure them. When you click on the angles, a protractor appears! As practice, learners view a set of angles, estimate the size of each, and then enter the degrees in...
MathMovesU
Practice: Measuring Angles and Using a Protractor and More!
Four fabulous worksheets are included in this resource, all having to do with the measurement of angles. On the first, anglers will use a protractor to determine the degrees of 10 different angles. An arc is drawn on each. On the second,...
K12 Reader
What’s Your Angle?
Start out with angles by asking your pupils to read this reading passage. Class members will learn about degrees, right angles, acute angles, and obtuse angles and then respond to five questions about the text.
Illustrative Mathematics
Right Triangles Inscribed in Circles II
So many times the characteristics of triangles are presented as a vocabulary-type of activity, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...
Alabama Learning Exchange
Unit Circle: Special Angles—Just Know One
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.
K12 Reader
Kinds of Angles
Have you ever wondered how circles and angles relate to each other? Read a passage about right angles, acute angles, and obtuse angles, and answer reading comprehension questions about the information you learn.
EngageNY
Inscribed Angle Theorem and Its Applications
Inscribed angles are central to the instructional activity. Young mathematicians build upon concepts learned in the previous instructional activity and formalize the Inscribed Angle Theorem relating inscribed and central angles. The...
Curated OER
Making an Angle Eater
Third graders create angle eaters where they use circles with cut outs to identify right, obtuse, and acute angles. Students complete 1 angle eater.
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 instructional activity to investigate angles created by secant lines that intersect at a point exterior to...
EngageNY
From Circle-ometry to Trigonometry
Can you use triangles to create a circle? Learners develop the unit circle using right triangle trigonometry. They then use the unit circle to evaluate common sine and cosine values.
Mt. San Antonio Collage
Circles
Don't circle around the topic, but get right to the center with tons of practice regarding circles in geometry. The note-incorporated learning exercise provides guided practice through many topics such as central angles, inscribed...
Illustrative Mathematics
Right Triangles Inscribed in Circles I
One of the basic properties of inscribed angles gets a triangle proof treatment in a short but detailed exercise. Leading directions take the learner through identifying characteristics of a circle and how they relate to angles and...
Curated OER
Measure and Draw Angles
Six word problems provide practice for young geometers to review angles, the angle a of straight line, circles, right angles, and others. I like the approach of these questions; they require thinking and explaining, not just computation.
Curated OER
Year 5 Unit 2b
This slide-show is packed with information relating to a variety of mathematical concepts. Intended as an accompaniment to a full unit, this resource provides definitions, explanations, and opportunities for learners to practice their...
Mathematics Assessment Project
Inscribing and Circumscribing Right Triangles
High schoolers attempt an assessment task requiring them to find the radii of inscribed and circumscribed circles of a right triangle with given dimensions. They then evaluate provided sample responses to consider how to improve their...
Math Mammoth
Measuring Angles
The first of two pages displays various angles as the measure of degrees of a circular arc. An explanation is written, and learners are asked to model each by holding up two pencils as the rays. The second page provides instruction on...
Curated OER
Angles
Here is a well-designed presentation on different types of angles for your young geometers. In it, learners view slides that clearly illustrate what these angles are, and how they are formed. Excellent practice when introducing these...
Illustrative Mathematics
Slopes and Circles
An upper-level treatment of what is often presented as a basic concept (the right angle of an inscribed circle on the diameter), this activity really elevates the mathematical thought of the learner! Expected to develop formulas from...
Curated OER
Circles and Angles
Students identify tangents, chords and secants. In this geometry lesson plan, students graph circles and identify angles created by secant lines, tangent lines and chords.