Curated OER
Attributes of Shapes Guided Lesson Explanation
Triangles, circles, and rectangles are featured in a colorful, one-page worksheet that defines and illustrates these shapes. Read the explanations with your first graders and have them count the number of shapes in a given box. Since the...
Curated OER
You Can't Go Wrong with a Right Triangle 2
Upper graders use the properties of right angle trignonmetry to measure objects such as the school flagpole. They solve real world problems using these properties.
Curated OER
Isosceles Triangle Theorem
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.
Curated OER
Identifying Angles
Students identify names of angles. They use a large clock to demonstrate angles using certain times of day. Given a geoboard, students create figures with acute, right, and obtuse angles.
Curated OER
Special Segments is a Triangle
In this geometry worksheet, 10th graders examine the special segments that occur in a triangle. The three page worksheet contains twenty-five problems. Answers are not included.
Lockport City School District
Reasons for Geometric Statement/Reason Proofs
Stuck trying to remember the formal language of a geometric proof? Never fear, this handout has them all ready to go. The reasons are sectioned by topic so this handy guide is ready when you are to tackle those two column proofs.
Curated OER
Analyzing Congruence Proofs
Looking at numerous examples of triangles, each with different properties, geometers develop their understanding of congruency. They use the notation of a counter-example to disprove certain conjectures and prove geometric theorems and...
Curated OER
Review Geometry - Week 8 (Triangles)
In this triangle worksheet, students use similar figures to find the length of one side of two similar triangles. They find the area of a triangle inscribed in a rectangle. This two-page worksheet contains eight problems.
Curated OER
Drawing a Triangle with Cabri Junior
Learners draw triangles on their graphing calculators using the Cabri Junior application. In this graphing calculator lesson, students follow step by step directions to create triangles on their calculator. They identify the type of...
Curated OER
Measuring Angles with a Protractor
In this measuring angles worksheet, students solve and complete 3 various types of problems. First, they complete each statement by measuring each angle shown. Then, students measure all three angles in a triangle and add them.
Curated OER
Value of Triangles
In this geometry activity, students identify the missing sides and angles of triangles. They find the midsegment of each triangle. There are nine questions with an answer key.
Curated OER
Special Right Triangles
Students identify the different parts of a right triangle. In this geometry lesson, students use the Pythagorean Theorem to identify missing sides and angles of a right triangle. They work with irrational and rational roots.
Curated OER
Angles and Similarity
High schoolers identify triangles as similar or congruent. In this geometry lesson, students drag triangles around on the navigator to see the effect of different angles on the shape of the triangle. They discuss angle similarity and...
Curated OER
Triangle Inequality Theorem
Learners use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
EngageNY
The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice...
Curated OER
Tile Patterns II: Hexagons
After learning that the sum of interior angles for triangles is 108 degrees, take it further to show that the sum of angles in any polygon is the same! Using hexagons, pupils practice finding the measure of the six congruent angles. Make...
EngageNY
End-of-Module Assessment Task: Pre-Calculus Module 4
Challenge your scholars to show what they know about the Law of Sines, Law of Cosines, and inverses. The six-question assessment is the last in a series of 16. Pupils find the area of triangles and show that the Law of Sines and Law of...
Curated OER
Inscribing a Hexagon in a Circle
This activity is a follow-on activity to inscribing a square in a circle. The overall problem is more complex. It deals with geometric constructions, properties of triangles, and regular hexagons. The final part of the activity...
Digging Into Math
Classifying Triangles
Young mathematicians explore the world of three-sided shapes in this lesson on the different types of triangles. Starting with a general introduction to classification using Venn diagrams, children learn how to categorize triangles...
Curated OER
Inscribing a Square in a Circle
Inscribing a square in a circle brings up a number of interesting geometry topics including triangle congruence and how to prove a quadrilateral is a square. This activity is followed up by finding the area of the square and determining...
101 Questions
Marine Ramp
Boat ramps move with waves and changes in water level. Scholars decide on the proper length for a ramp so the angle connecting both sides is appropriate. They visualize the situation and use a simulation to view the results with their...
EngageNY
Pythagorean Theorem, Revisited
Transform your pupils into mathematicians as they learn to prove the popular Pythagorean Theorem. The 16th lesson plan in the series of 25 continues by teaching learners how to develop a proof. It shows how to prove the Pythagorean...
Los Angeles County Office of Education
Assessment for the California Mathematics Standards Grade 5
Test young mathematicians' knowledge with an assessment aligned to California's fifth grade state standards. The exam covers a multitude of concepts including fractions and decimals, positive and negative numbers, measurement; and...
Mathed Up!
Loci and Constructions
A General Certificate of Secondary Education math review has class members make basic constructions. Using a protractor and a ruler along with a compass, pupils develop drawings of triangles with given measurements. Scholars use their...