Activity
Curated OER

Inscribing a Square in a Circle

For Teachers 9th - 11th Standards
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...
Lesson Plan
EngageNY

Law of Cosines

For Teachers 11th - 12th Standards
Build upon the Pythagorean Theorem with the Law of Cosines. The 10th part of a 16-part series introduces the Law of Cosines. Class members use the the geometric representation of the Pythagorean Theorem to develop a proof of the Law of...
Lesson Plan
Curated OER

Pythagoras' Theorem

For Teachers 8th - 12th
Students are introduced to the Pythagoras' Theorem and its history, proofs and practice in application. Students find perimeters, areas and volume of everyday objects. Students state and explain the theory.
Worksheet
Curated OER

Nets and Surface Area - Mental Math

For Students 6th - 8th
In this mental math learning exercise, middle schoolers use mental math to find the surface area and determine nets of the given shape. They use an information sheet as an aide to find the answer to 30 questions.
Worksheet
Curated OER

Calculating the Area of a Triangle

For Students 5th
A quick definition and the formula for finding the area of a triangle is provided at the top of this worksheet. After reading the description, 5th graders must find the area of the 3 given triangles. This is an excellent enrichment...
Lesson Plan
Curated OER

Area of Polygons

For Teachers 10th
In this area of polygons worksheet, 10th graders solve and complete 8 various types of problems. First, they graph each line and find the area of each enclosed triangle. Then, students determine the ordered pairs of each graph illustrated.
Assessment
Concord Consortium

Three Rubber Bands

For Students 7th - 12th Standards
Stretch your mind about triangles. Given a triangle, scholars consider a smaller triangle formed when they stretch three rubber bands from each vertex to the opposite side. They determine the ratios of the areas and perimeters of the...
Lesson Plan
Curated OER

Inscribing a Circle in a Triangle

For Teachers 9th - 12th Standards
Pupils investigate inscribing a circle in a triangle. They use Cabri Jr. to draw a triangle, locate the incenter, and use the distance from the incenter to a side of the triangle to inscribe a circle. The dynamic nature of the geometry...
Lesson Plan
Curated OER

Geometry, Measurement & Reasoning

For Teachers 7th - 9th
Learners measure prisms and determine their volume. In this measurement and reasoning lesson, students estimate the volume and area of prisms. They measure given boxes. Learners use paper to create prisms and cylinders. They determine...
Lesson Plan
Curated OER

Reflecting a Triangle in the Coordinate Plane

For Teachers 9th - 12th Standards
Learners explore geometric concepts using technology. They manipulate the TI to find important math topics. This activity requires a TI-84 or higher.
Lesson Plan
Curated OER

Scale Factor Area Perimeter

For Teachers 9th - 12th Standards
Mathematicians compare triangles at different scales. In this geometry lesson, young scholars calculate the area and perimeter of triangles. They use the Ti to make observation of the change that takes place as the triangles are dilated.
Lesson Plan
Curated OER

Properties of the Centers of a Triangle

For Teachers 9th - 12th Standards
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.
Worksheet
Curated OER

Bermuda Triangle: Map Activity

For Students 4th - 5th
In this Bermuda triangle worksheet, students complete a set of 4 questions using a given map of the Bermuda triangle. Answers are included on page 2.
Worksheet
Curated OER

Area and Perimeter of Triangles

For Students 5th - 6th
In this area/perimeter worksheet, learners find perimeter and area of 6 given triangles. An answer key is included on page 2.
Lesson Plan
Curated OER

Perimeter and Area of Rectangles

For Teachers 6th
Sixth graders solve for the area and perimeter. In this geometry lesson, 6th graders investigate polygons and use a formula to find the area and perimeter. They find the area and perimeter of various polygons.
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.
Worksheet
Curated OER

Perimeter and Area

For Students 4th - 6th
In this perimeter and area worksheet, students find area and perimeter of 9 triangles. A website reference is given for additional resources.
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.
Worksheet
Curated OER

Perimeter and Area #6

For Students 4th - 6th
In this perimeter/area worksheet, students find area and perimeter for a set of 9 triangles. A website reference is given for additional activities.
Lesson Plan
1
1
Cord Online

Pyramids and Cones

For Teachers 8th - 11th Standards
Young mathematicians find the surface area and volume of a square pyramid and a cone. In what looks like a typical activity out of a textbook, you'll find an activity where learners find an unknown measurement of a pyramid or...
Worksheet
Geometry Accelerated

Coordinate Geometry Additional Practice

For Students 8th - 10th Standards
Your learners get extra practice using coordinates in calculating mid points, finding end points, deciding if points are collinear, calculations using slope concepts, writing linear equations, using triangles and quadrilaterals, and...
Lesson Plan
Curated OER

Worksheet 8 - Vectors

For Teachers Higher Ed
In this vector worksheet, students find the area of a parallelogram spanned by vectors, they give the geometric and algebraic definitions of the dot product and describe a sequence of vectors. This one-page worksheet contains six...
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.