Lesson Plan
Curated OER

The Laws of Sines and Cosines Made Simple!

For Teachers 10th - 12th
Students study the law of sine and cosine. For this pre-calculus lesson, students create a triangle and identify the different ratios of a non-right triangle. They use the properties of sine and cosine to solve.
Lesson Plan
Curated OER

Positive and Negative Angles and Arcs

For Teachers 9th - 12th Standards
To better understand that the intersection point of two lines lies inside a circle, learners use their keen measurement skills. They discuss arcs, rays, tangent lines, and reflex angles. Then, they put their skills to work as they...
Worksheet
Curated OER

Measuring Angles

For Students 6th - 7th
In this math worksheet, students use protractors to measure each of a set of angles. This is a worksheet generator, the teacher controls the minimum and maximum angles students are presented with as well as whether or not to rotate...
Lesson Plan
Curated OER

Angles

For Teachers 7th - 12th
Students measure angles using a protractor. In this geometry lesson, students solve for the missing angles using equations set to the theorem of triangles. They measure missing angles through construction and identify congruent angles.
Worksheet
Curated OER

Special Triangles and Quadrilaterals

For Students 9th - 11th
In this special triangles worksheet, students examine given special triangles.  They determine the length of a missing side and/or the measurement of a missing angle for given triangles and quadrilaterals.  Students justify...
Lesson Plan
Curated OER

Perpendicular Bisector of a Line Segment

For Teachers 9th - 12th Standards
High Schoolers investigate the perpendicular bisector of a line segment. They use Cabri Jr. to construct the perpendicular bisector of a segment. The dynamics capabilities of Cabri Jr. allow your learners to observe the lengths of the...
Worksheet
Curated OER

Geometry: Properties of Triangles

For Students 10th - 12th
For this properties of triangles worksheet, students use their knowledge of triangles to find determine angle measurement. They use geometric theorems to prove equal angles. This three-page worksheet contains 15 multi-step geometry...
Worksheet
Curated OER

Arc and Angles Formed by Secants and Tangents

For Students 9th - 11th
In this calculus worksheet, students solve problems by finding the line of tangency and measure of the arcs and angles form by a secant line. There are 9 questions.
Worksheet
Math Mammoth

Area of Rectangles

For Students 4th
In this geometry worksheet, 4th graders identify how many square units is the area of each of the shaded shapes. Then they find the areas of the rectangles when the sides are given. Students also draw the figure described for each.
Lesson Plan
EngageNY

Triangle Congruency Proofs (part 2)

For Teachers 9th - 10th Standards
Looking to challenge your young scholars that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs...
Lesson Plan
Hotchalk

Triangle Sum Theorem

For Teachers 8th - 10th Standards
Your visual geometry learners will appreciate triangle drawings as they model the triangle sum theorem and algebraically solve to find the missing interior angle in a triangle. Practice problems increase in complexity and vary in their...
Lesson Plan
Curated OER

Geometric Properties

For Teachers 9th - 12th
Students find triangular angles using the angle theorem. In this geometry lesson, students describe labeled triangles, use the pythagorean theorem, and rewrite information about triangles in standard form.
Worksheet
Curated OER

Law of Sines

For Students 10th
In this Law of sines worksheet, 10th graders solve 10 different sets of problems related to the Law of Sine and Ambiguous case. First, they determine the ratio of the sides of the triangle with the given measurements. Then, students...
Interactive
Scholastic

Study Jams! Similar Figures

For Students 5th - 8th Standards
Discover how triangles are congruent based on their sides, angles, and proportionality. Learners explore the ways to determine similarity at their own pace, and then they practice afterwards with an assessment. 
Lesson Plan
Curated OER

My Angle on Cooling: Effects of Distance and Inclination

For Teachers 6th - 8th
Middle schoolers discuss what heat is and how it travels. They discover that one way to cool an object in the presence of a heat source is to increase the distance from it or change the angle at which it is faced.
Lesson Plan
Curated OER

Toothpick Triangles

For Teachers 4th - 8th
Learners draw a chart (included in the lesson) to use with their investigation. They review terminology of triangles and receive toothpicks to use in the lesson. Beginning with three toothpicks, students form a triangle. They complete...
Assessment
Mathematics Assessment Project

Octagon Tile

For Teachers 6th - 8th Standards
A connecting-the-dots activity seems too easy for seventh grade but connecting vertices may prove a challenge. Class members first examine a figure created by drawing squares around the inside of an octagon and connecting the...
Performance
Radford University

How Tall Is It?

For Teachers 9th - 12th Standards
Find the height from afar. Teams role play as summer interns to find the height of a set of windows from the outside. Scholars must first determine how to find the height with the available tools. After determining a strategy involving...
Workbook
1
1
University of Utah

Geometry: Transformations, Congruence, and Similarity

For Students 8th Standards
Rigid motions are to congruence as what are to similarity? Investigate properties of rigid motions and define congruence in terms of rigid motions with the ninth chapter of a 10-part eighth grade workbook series. The...
Worksheet
Curated OER

Supplementary Angles (B)

For Students 5th
In this geometry worksheet, 5th graders identify the missing angle measurement in each set of supplementary angles. They find the angle measurement in 8 examples.
Worksheet
Curated OER

Supplementary Angles (A)

For Students 5th - 6th
In this supplementary angles worksheet, learners solve 4 problems in which the missing angle measurement in a set of supplementary angles is calculated.
Lesson Plan
Curated OER

Arc Measurement Based on The Measurement of a Central Angle

For Teachers 9th - 10th
Students define keywords that are important to solve problems. In this geometry instructional activity, students find the arc length and angle of a circle. They convert between radians and degrees.
Worksheet
Curated OER

Angles on a Line and on a Point

For Students 6th - 7th
In this angles worksheet, learners solve 24 problems pertaining to angle measurements on a line and on a point. There are also calculations of adjacent angles and supplementary angles. The page is intended as an online activity but can...
Worksheet
Curated OER

Measuring Angles

For Students 10th
In this measuring angles worksheet, 10th graders solve and complete 26 various types of problems. First, they use a protractor to find the measurement of each angle. Then, students state the Angle Addition Postulate for the three angles...