Interactive
Noetic Learning

Kinds of Triangles (Online Interactive)

For Students 3rd - 4th
In this triangles learning exercise, students analyze pictures of four triangles. For each triangle, students mark if it is acute, obtuse, or right.
Lesson Plan
Curated OER

Which Way Do I Go? (Identifying Angles)

For Teachers 5th
Fifth graders practice the concepts related to finding and identifying different angles. There are examples included in the lesson that are useful for the teacher to deliver the lesson.
Lesson Plan
Curated OER

Daily Upkeep 1

For Teachers 4th
In this math review worksheet, 4th graders read a graph and identify the amount of money earned during a specific week. Then they solve a word problem using multiplication or addition. Finally, students identify which angle shown is best...
Lesson Plan
Curated OER

Pythagorean Theorem: Triangles and Their Sides

For Teachers 8th - 10th
Students investigate triangles and their relationship to each other. For this geometry lesson, students solve right triangles using the properties of the Pythagorean Theorem. They differentiate between right, acute, straight and oblique...
Lesson Plan
Houghton Mifflin Harcourt

Introducing the Concept: Triangles and Quadrilaterals

For Teachers 5th - 7th Standards
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...
Lesson Plan
Curated OER

Isosceles Triangles

For Teachers K - 2nd
Students investigate triangles. In this shapes geometry lesson, students define and state the attributes for equilateral, scalene, and isosceles triangles. Students locate the prefix "tri" in a variety of words and make connections with...
Worksheet
K12 Reader

Classifying Triangles

For Students 2nd - 3rd Standards
Bring math and reading informational text together with a reading comprehension lesson. After kids read about isosceles, scalene, and equilateral triangles, they answer five comprehension questions to demonstrate how they can use context...
Instructional Video12:58
2
2
Flipped Math

Pythagorean Theorem and Its Converse

For Students 9th - 12th Standards
Make sure it is all right in class. Pupils review the Pythagorean Theorem and find sides of right triangles, either by simplifying radicals or using calculators to find approximate lengths. Learners find out how to use the converse to...
Lesson Plan
Curated OER

The Pythagorean Theorem and Classifying Triangles

For Teachers 9th - 12th Standards
Through the examination of the relationship between the lengths of the sides of a triangles high schoolers will learn the classification of triangles (acute, right, or obtuse).
Interactive
Curated OER

My Test Book: Geometry

For Students 3rd - 4th
In this online interactive math skills worksheet, students solve 10 multiple choice math problems regarding geometry skills. Students may view the correct answers.
Worksheet
Curated OER

Parts of Similar Triangles

For Students 10th
In this parts of similar triangles worksheet, 10th graders solve and complete 15 different statements related to naming the parts found in similar triangles. First, they identify each definition stated that describes an everyday usage of...
Lesson Plan
Curated OER

Identifying Triangles

For Teachers 6th
Sixth graders identify and define a variety of triangles. In this identification of triangles lesson, 6th graders draw examples of each triangle on a whiteboard, then complete a worksheet.
Lesson Plan
Curated OER

Geoboard Ideas

For Teachers 3rd - 4th
Learners build polygons on their geoboards. For this geometry lesson plan, students build and then draw it on paper and label it. Learners then switch with a partner to try an make a symmetrical shape.
Worksheet
Math Mammoth

Triangles

For Students 6th - 8th Standards
A six-page packet walks, or bends learners through angles that combine to create triangles. Definitions are given for right triangles, obtuse and acute triangles. They draw angles according to directions, using a protractor to meet the...
Worksheet
Curated OER

Extending Trigonometry Skills

For Students 10th - 12th
For this trigonometry worksheet, students use the sine and cosine law to solve problems. They investigate obtuse triangles using these laws. There are 40 questions.
Worksheet
Raytheon

Understanding Triangles

For Students 6th - 8th
In this understanding triangles worksheet, middle schoolers read 6 pages of examples and explanations about identifying triangles, determining length of sides and degrees of angles, including the hypotenuse, then answer 28 questions,...
Lesson Plan
Curated OER

Contructions and Conjectures

For Teachers 10th - 11th
Students make constructions and conjectures. In this geometry lesson, students construct right, acute and obtuse angles using a straight edge and a protractor. They investigate parallel lines and the angles formed by the angles.
Worksheet
Curated OER

Geometry Vocabulary

For Students 10th
In this geometry vocabulary worksheet, 10th graders are given different angles with different names. They must match the correct angle with the correct name. There are 45 questions dealing with angles, there is an answer key.
Assessment
Bowland

Rods and Triangles

For Teachers 6th - 9th
Scholars explore triangles with rods of different lengths. Using rods of 2, 4, 6, 8, and 10 cm class members build as many different types of triangles as they can. They also describe properties of these triangles and determine...
Lesson Plan
Willow Tree

Common Geometric Figures

For Students 8th - 11th Standards
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons. 
Interactive1:45
Scholastic

Study Jams! Classify Triangles

For Students 5th - 8th Standards
Jam on with this multi-faceted activity teaching triangle classification. Start with a learner-paced lesson describing the different qualities of triangles and follow with a fun karaoke session. Also provided are two types...
Worksheet
Curated OER

List of Geometry Terms

For Students 4th - 9th
In this angle vocabulary card instructional activity set, students identify the vocabulary associated with angles such as: ray, vertex, acute angle, segment bisector, and corresponding angles. They identify 23 terms but there are no...
Worksheet
Curated OER

Identify Triangles #3

For Students 3rd - 5th
In this triangle activity, students identify triangles as obtuse, right, or acute, checking the correct answer. A reference web site is given for additional activities.
Lesson Plan
Curated OER

Picking Pythagoras

For Teachers 6th - 9th
Students discover that side measurement is used in determining angle classification of a triangle. By squaring sides, they predict whether triangles be right, obtuse, or acute. They prove the Pythagorean Theorem and use it to solve...