PPT
Curated OER

#### Isosceles Triangles

For Teachers 4th - 5th
In need of a fun way to define an isosceles triangle? This activity has learners fold a paper in half and then cut it to create an isosceles triangle. They determine the line of symmetry by folding the triangle in half and then use the...
Lesson Plan
Curated OER

#### Geometry Journal: Isosceles Triangles

For Teachers 10th - 12th
In this isosceles triangles worksheet, students justify and determine the symmetry of an isosceles triangle. They explore the bisector of rectangles. This three-page worksheet contains two problems. Answers are listed on page three.
Instructional Video6:29
Corbett Maths

#### Pythagoras Rectangles and Isosceles Triangles

For Students 7th - 12th Standards
When does the Pythagorean Theorem come in handy? An intriguing video uses the Pythagorean Theorem to solve problems other than simply finding the length of a side of a right triangle. Pupils find the diagonal of a rectangle and the...
Lesson Plan
Curated OER

#### Isosceles Triangle Theorem

For Teachers 8th - 10th
In this geometry worksheet, students differentiate between regular triangles and isosceles triangles. They apply the converse theorem and the vertex angle. There are eleven questions with an answer key.
Worksheet
Mt. San Antonio Collage

#### Isosceles Triangles and Special Line Segments

For Students 9th - 12th Standards
Under which conditions can a triangle be classified as isosceles? High schoolers practice identifying isosceles triangles and special line segments, including angle bisectors, medians of triangles, and perpendicular bisectors of sides of...
Lesson Plan
EngageNY

#### Base Angles of Isosceles Triangles

For Students 9th - 10th Standards
Build confidence in proofs by proving a known property. Pupils explore two approaches to proving base angles of isosceles triangles are congruent: transformations and SAS. They then apply their understanding of the proof to more complex...
Worksheet
Curated OER

#### Classifying Triangles Using Sides

For Students 4th - 5th
In this geometry learning exercise, students answer 8 fill in the blank questions where they must examine 5 different complex geometric figures to classify triangles.
Assessment
Concord Consortium

#### Isosceles Triangle Spaces

For Students 7th - 10th Standards
How many different types of triangles can your class name? A discovery lesson guides learners through an exploration of the different triangle types and the relationships between their angles and sides. Using coordinate geometry,...
Lesson Plan
Curated OER

#### Triangles

For Teachers 5th - 6th
In this math worksheet, students answer 3 questions about an equilateral triangle. Students then answer 3 questions about isosceles triangles. Students then calculate missing angles on isosceles triangles.
Lesson Plan
Curated OER

#### How many isosceles Triangles Can You Find?

For Teachers 5th
Fifth graders solve problems while examining a variety of isosceles triangles.  In this isosceles triangle lesson, 5th graders examine shapes to find their characteristics.  Students pay particular attention to the characteristics of...
Lesson Plan
Curated OER

#### How many isosceles triangles can you find?

For Teachers 7th
Seventh graders recognize the characteristics of isosceles triangles. In this isosceles triangle lesson, 7th graders use geoboards to create isosceles triangles. Students record results and explain why they have an isosceles triangle.
Lesson Plan
Curated OER

#### Geometry Regents Questions: Isosceles Triangle Theorem

For Teachers 9th - 12th
In this isosceles triangle worksheet, students solve 19 multiple choice and short answer problems.  Students use the isosceles triangle theorem to determine unknown angle measures.
Worksheet
Curated OER

#### Isosceles Triangles

For Students 9th - 12th
In this geometry worksheet, learners set up equations to solve for the missing angle or side of an isosceles triangle. All the equations turn out to be linear and not quadratic. There are 15 questions.
Lesson Plan
Alabama Learning Exchange

#### What You Know About the Bermuda Triangle?

For Teachers 9th - 12th Standards
Get lost in the classifications. Using the backdrop of the Bermuda Triangle, pupils classify it by angle and side measures. They also learn information about the triangle and its history.
Lesson Plan
2
2
Curated OER

#### Two Triangles' Area

For Teachers 7th - 9th Standards
Need an activity for teaching the Pythagorean Theorem? Geometry juniors apply the Pythagorean theorem to two triangles to determine a final calculation.
PPT
Curated OER

#### Classifying Triangles

For Teachers 3rd - 5th
If you're looking for a presentation to assist you in your teaching of triangles, this one could be for you. In it, learners are shown how triangles are classified by the size of their angles and by their sides. These are tricky concepts...
Lesson Plan
Illustrative Mathematics

#### Lines of Symmetry for Triangles

For Teachers 3rd - 5th Standards
What can symmetry tell us about triangles? After looking at four examples, learners will come to realize that lines of symmetry are different for equilateral, isosceles, and scalene triangles. Use this guided practice activity as an...
Handout
McGraw Hill

#### Triangles

For Students 4th - 7th Standards
After reviewing characteristics of seven types of triangles, young geometers discover how to find the missing angle of a triangle. Then, they practice identifying triangles, find missing angles, and find missing side lengths of similar...
Printables
K-5 Math Teaching Resources

#### Triangle Pack

For Teachers 4th - 6th Standards
With so many different types of triangles, it can be a challenge for young mathematicians to keep them all straight. Luckily this set of printable triangles is here to engage children in comparing and sorting triangles by their...
Lesson Plan
Curated OER

#### Sea Squares

For Teachers 10th
In this sea squares worksheet, 10th graders solve 5 different problems that include various geometrical figures. First, they draw a number line using one color. Then, students draw 2 obtuse angles and 3 isosceles triangles with different...
Lesson Plan
Curated OER

#### Isosceles Triangle Theorem

For Teachers 8th - 9th
In this geometry worksheet, learners differentiate between isosceles and regular triangles. They calculate the area and perimeter of the triangle. There are eleven questions with an answer key.
Lesson Plan
Curated OER

#### Geometry of Triangles - Week 6

For Teachers 10th - 12th
For this triangle worksheet, students explore the characteristics of triangles. They find the area of a pentagon, lengths of the sides of a triangle and the area of a quadrilateral. This two-page worksheet contains seven problems.
Worksheet
Curated OER

#### Classification of Triangle Measurement & Perimeter

For Students 10th
In this classification of triangles activity, 10th graders identify and complete 8 different problems that include determining the measurement and perimeter of various types of triangles. First, they color all right, acute, and obtuse...
Worksheet
Curated OER

#### Isosceles Triangles

For Students 3rd - 4th
In this isosceles triangles worksheet, students cut or count the triangles on this sheet. Students cut or count out 13 isosceles triangles that are all different colors.