Curated OER
8th Grade Math Classifying Triangles and Quadrilaterals
Eighth graders engage in a lesson plan that is about classifying polygons with the focus being upon specific triangles and quadrilaterals. They conduct activities using cutouts for kinesthetic learners to help make connections while...
Curated OER
Congruent Triangles Postulates
Students discover three lettered postulates that prove triangles congruent.
Curated OER
Proving Triangles Congruent
Students examine Triangle Congruency. In this measurement comparison lesson, students use inductive, deductive and analytical thinking skills to prove triangle congruency. Students analyze and record their findings on activity worksheets.
Curated OER
Triangles in Architecture
Students find triangles in the real world. In this geometry lesson, students analyze and identify properties of two and three-dimensional objects. They differentiate between similarity and congruence.
Curated OER
Special Right Triangles
Students identify the different parts of a right triangle. In this geometry instructional activity, students use the Pythagorean Theorem to identify missing sides and angles of a right triangle. They work with irrational and rational roots.
Houghton Mifflin Harcourt
Introducing the Concept: Triangles and Quadrilaterals
Guide your geometers through the process of constructing polygons. They learn how to draw triangles, squares, parallelograms, rectangles, rhombuses, and trapezoids with specified angles using a protractor and a ruler. The lesson plan...
Curated OER
Polygons
Students investigate the concepts related to the study of polygons. They specifically look at how angles is related. The lesson includes specific examples and dialogue to be used by the teacher during direct instruction and independent...
Curated OER
Discover the Pythagorean Theorem
Learners explore the Pythagoras theorem. In this geometry lesson, students make right triangles and identify the parts of the triangle. Learners complete measurements of the sides of the triangle.
EngageNY
Solving Problems Using Sine and Cosine
Concepts are only valuable if they are applicable. An informative resource uses concepts developed in lessons 26 and 27 in a 36-part series. Scholars write equations and solve for missing side lengths for given right triangles....
West Contra Costa Unified School District
Law of Sines
One must obey the sine laws. A lesson introduces and derives the Law of Sines for non-right triangles. With examples that use the Law of Sines to determine unknown measures in triangles, the lesson checks to see if the Law...
Curated OER
How are Trig Ratios Used to Measure Triangle Sides
Students identify the ratios of trig identities. In this geometry lesson, students solve the missing sides and angles of triangles using trig ratios. They relate the graphs and waves to real life scenarios.
Houghton Mifflin Harcourt
Developing the Concept: Triangles and Quadrilaterals
Exact narrative and examples make this lesson on polygons easy to implement. Through it, your class will learn how to use a protractor and ruler to construct triangles and quadrilaterals according to your directions. Your class will be...
Improving Measurement and Geometry in Elementary Schools
The Sum of the Interior Angles of a Polygon
Junior geometers discover that polygons can be decomposed into triangles and that the number of triangles can be determined by a rule. Note that the Geometer’s Sketchpad® software is required to carry out all components of this...
Curated OER
Triangle Side Lengths and Angles Measures
Students identify missing sides and angles. In this geometry lesson, students use triangular theorems to identify the missing sides. They use the Pythagorean Theorem to find the different ratios of each side.
Curated OER
Physics Lab Rockets
Learners construct and test balloon rockets and a model rocket. In this rocket science activity, students use an inquiry-based method to master balloon rockets and have a shoot-off with the goal of attaining the highest altitude. Next,...
Curated OER
Algebra 2 & Trigonometry Practice: Law of Sines
In this law of sines worksheet, high schoolers solve 9 multiple choice and short answer problems. Students use the law of sines to missing side lengths and angles of triangles.
Curated OER
Tessellation Trial and Error
In this interactive instructional activity, students review attributes of equilateral polygons. They are introduced to the concept of a tessellation. Using protractors and pre-cut shapes, students arrange a variety of tiles to create...
Curated OER
Properties of the Centers of a Triangle
High schoolers investigate properties of the four centers of a triangle and explore a special property of the circumcenter and orthocenter of a triangle. This lesson requires the use of Cabri, Jr.
Curated OER
Triangles with Collinear Circumcenters
Students identify the circumcenter of a triangle. In this geometry lesson, students construct a perpendicular bisector using a straight edge and a compass. They differentiate between triangles and collinear points.
Curated OER
Twenty-Five Measures of the Angles of a Triangle Problems
In this triangle worksheet, pupils calculate the measures of the angles or the sums of the measures of the angles in twenty-five triangle problems and hands-on activities. The solutions are provided.
Curated OER
Triangle Exterior Angles Theorem
Students identify the measure of missing exterior angles. In this geometry lesson,students define and apply the exterior angle theorem to solve problems. They use Cabri software to create different angles and make investigations.
Curated OER
Whatcha Gunna Do When the Hulkster's Measuring Too??
Students measure using tools they have made. In this algebra lesson, students measure the height and distance using non-traditional measuring methods. They apply their findings to algebra and trigonometry properties of measurements.
Curated OER
Exploring Angle Pair Relationships
Learners investigate the relationship between angles of triangles. In this geometry lesson, students identify properties of right and non-right triangles. They differentiate between vertical and supplementary angles.
Curated OER
Triangles Introduction
Students explore geometry by drawing various shapes in class. In this triangle characteristics lesson, students identify the attributes that classify a shape as a triangle and practice using their bodies to create triangles in class....