Lesson Plan
Curated OER

Triangles with Collinear Circumcenters

For Teachers 9th - 10th
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.
Lesson Plan
Curated OER

Twenty-Five Measures of the Angles of a Triangle Problems

For Teachers 9th - 10th
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.
Interactive
Curated OER

A Trying Triangle Problem

For Students 8th - 10th
In this geometry worksheet, students calculate the length of the sides of a given triangle. They also find the perimeter and area of the triangles given its side values. There is an answer key with this problem.
Lesson Plan
Curated OER

Why can't We Use SSA to Prove Triangles Congruent?

For Teachers 9th - 10th
Students investigate triangles and congruences. In this geometry lesson, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.
Lesson Plan
Curated OER

Isosceles Triangle Investigation

For Teachers 9th - 12th
Pupils solve problems with isosceles triangles. In this geometry lesson, students identify and use the properties of triangles to solve their problems. They find the median, altitude, and angles to the triangles.
Worksheet
Curated OER

Area and Perimeter of Various Shapes

For Students 5th - 6th
In this area and perimeter worksheet, students find each for 6 given shapes. A website reference for additional resources and an answer key are provided.
Lesson Plan
Curated OER

Areas of Polygons

For Teachers 8th - 10th
Students calculate the are of regular polygons. In this geometry lesson, students create polygons on the computer and move it around to create different shapes. They explore the area of different polygons and how they inter-relate.
Lesson Plan
Curated OER

Area of irregular Polygons: Historical Motivator - Lewis and Clark Adventure

For Teachers 7th
Seventh graders find the area of irregular polygons. In this lesson on calculating area, 7th graders use the adventures of Lewis and Clark as motivation to learn how to calculate the area of irregular polygons.
Lesson Plan
Curated OER

PRE ALGEBRA

For Teachers 8th
Eighth graders find missing angles of triangles, quadrilaterals and angles formed by parallel lines cut by a transversal. They use area formulas to find the area of a figure; find the complement and supplement of a given angle; and know...
Worksheet
Curated OER

Pythagorean Theorem

For Students 10th
In this Pythagorean Theorem activity, 10th graders solve and complete 19 various types of problems. First, they draw the square shown and divide its sections as shown. Then, students cut out the 6 parts of the square and rearrange the 4...
Worksheet
Curated OER

Geometry Take Home Question

For Students 9th - 12th
In this triangles, parallelograms, and kites worksheet, students solve 4 short answer problems. Kids find the area of the given triangle. Students construct parallelograms and kites by cutting out and manipulating the given triangles.
Worksheet
Curated OER

Similar Polygons

For Students 10th
In this similar polygons instructional activity, 10th graders solve 10 different problems that include determining various similar polygons. First, they determine the perimeter of a second triangle given the measures of all angles in the...
Lesson Plan
Curated OER

Area Unit

For Teachers 9th - 11th
Students solve the area for parallelograms,squares, rectangles, trapezoids, and triangles. In this geometry lesson, students compare and contrast two dimensional shapes and apply their properties to solving real life scenarios. This is a...
Worksheet
Curated OER

Geometry Course Review

For Students 10th
For this geometry review set of worksheet, 10th graders solve and complete 139 various types of problems. First, they find the slope-intercept form of a line passing through a point and parallel to a line given. Then, students find the...
Worksheet
Curated OER

Section 6.1-6.2 Precalculus: Trigonometry

For Students 9th - 12th
In this trigonometry worksheet, students solve 15 triangle problems.  Students use the law of sines and law of cosines to find the missing angles and side lengths of a triangles.
Lesson Plan
Curated OER

Up For Change?

For Teachers 7th - 9th
Students explore similar objects. They participate in a series of hands-on, multimedia and online activities to examine how the edge length affects the angle measures, perimeters and areas of similar regular polygons. Students find the...
Lesson Plan
Texas Instruments

What's the Trig?

For Teachers 9th - 12th Standards
Learners determine the trigonometric relationships within a triangle as they construct a right triangle on the Ti-89. They find the sine, cosine, and tangent of various angles of their triangle construction.
Lesson Plan
Curated OER

Using Cabri Geometry to Create Fractals

For Teachers 9th - 12th Standards
Learners construct the Sierpinski Triangle using Cabri Jr. They use a step-by-step guide to construct the Sierpinski Triangle on their graphing calculator and then discuss the formula for constructing a nth stage Sierpinski Triangle.
Worksheet
Curated OER

Geometry Standardized Test Practice

For Students 10th
In this angles and figures review worksheet, 10th graders solve and complete 39 different multiple choice problems. First, they find the length of a line between two given points. Then, students name the type of transformation and the...
Lesson Plan
Curated OER

Trig River

For Teachers 6th - 8th
Students calcute distances using trigonometry and angle measurements. They estimate the width of the Trig River, measure it and compare their results with their classmates. They collaborate with a group to research and find the results.
Worksheet
Math eBook

Perimeter Worksheet

For Students 7th - 8th
In this perimeter activity, learners find the perimeter of given regular and irregular polygons. This four-page activity contains 20 problems. This interactive activity may be completed online or printed for paper use.
Lesson Plan
Curated OER

Shapes and Introduction to Geometry

For Teachers 2nd - 4th
Students make a quilt. In this geometry instructional activity, students discuss patchwork quilts and learn some different geometric shapes and patterns that are commonly used. Students explore designs with triangles and squares and then...
Interactive
Curated OER

Tangents

For Students 10th - 12th
In this tangents learning exercise, students use tangent ratios to find the length of the sides of right triangles. This one-page learning exercise contains 10 multi-step problems.  Answers are provided.
Worksheet
Curated OER

Circles and Squares

For Students 9th - 12th
In this area activity, students find the ratio of 1 area problem.  Students find the ratio of areas of inscribed circles to circumscribed squares.