Curated OER
Area Unit
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...
Curated OER
Using Cabri Geometry to Create Fractals
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.
Texas Instruments
What's the Trig?
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.
Curated OER
IMAGE Satellite and Solar Cells
In this IMAGE satellite and solar cells worksheet, students calculate the surface area of the satellite in order to determine how much electrical power can be generated by the solar cells.
Curated OER
Congruent Trianges - Is This Enough Information?
Seventh graders determine whether two triangles are congruent and provide an explanation to why they are not. They apply concepts of measurement of angles and collect evidence of congruent angles in the world.
Curated OER
Perpendicular Bisector Theorem
High schoolers construct perpendicular bisectors using Cabri Jr. on their graphing calculator. They then construct conditional statements about perpendicular bisectors along with their converse, inverse, and contrapositive.
National Council of Teachers of Mathematics
Improving Archimedes' Method
For this Archmides' method instructional activity, learners determine the area of a regular n-gon inscribed in a circle. They use sine and cosine functions to solve problems. This three-page instructional activity contains 4 multi-step...
Curated OER
Midsegments of Quadrilaterals
High schoolers explore the concept of quadrilaterals as they find the midsegments of quadrilaterals using Cabri Jr. on a graphing calculator. They find midpoints, slopes, angles, and distances of lines and angles.
Texas Instruments
Getting Started with Cabri Jr.
Pupils construct geometric figures using Cabri Jr. in this constructing geometric figures using Cabri Jr. activity. They familiarize themselves with Cabri Jr. and construct segments and triangles. Your learners will use various tools to...
Curated OER
Tangents
In this tangents worksheet, students use tangent ratios to find the length of the sides of right triangles. This one-page worksheet contains 10 multi-step problems. Answers are provided.
Curated OER
Pythagorean Theorem
In this measurement activity, students will be given 2 sides of a right triangle, they will determine if the missing side is a leg or the hypotenuse. They will use the Pythagorean Theorem to create an equation and find the length of the...
Curated OER
In the Path of the Ancients: Unearthing Formulas for Area
Students apply the formulas for the area of parallelograms and triangles. Through guided practice, students discover the correct way to apply the formulas. Working in pairs, they write their own problems featuring the formulas.
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts to finding...
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
Virginia Department of Education
The Pythagorean Relationship
Add up areas of squares to discover the pythagorean relationship. Small groups create right triangles with squares along each side. They calculate the areas of each square and notice the relationship. Groups construct other types of...
Illustrative Mathematics
Extensions, Bisections and Dissections in a Rectangle
Gaining practice in translating a verbal description into a diagram and then an equation is the real point of this similar triangles exercise. Once the diagram is drawn, multiple methods are provided to reach the conclusion. An effective...
EngageNY
End-of-Module Assessment Task: Grade 7 Mathematics Module 6
Determine the level of understanding within your classes using a summative assessment. As the final lesson in a 29-part module, the goal is to assess the topics addressed during the unit. Concepts range from linear angle relationships,...
Geometry Accelerated
Coordinate Geometry Additional Practice
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...
EngageNY
Definition and Properties of Volume
Lead a discussion on the similarities between the properties of area and the properties of volume. Using upper and lower approximations, pupils arrive at the formula for the volume of a general cylinder.
Curated OER
Inscribing a Circle in a Triangle
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...
Curated OER
Scale Factor Area Perimeter
Mathematicians compare triangles at different scales. In this geometry lesson plan, high schoolers calculate the area and perimeter of triangles. They use the Ti to make observation of the change that takes place as the triangles are...
Curated OER
Investigating Area Using Tangrams
Tenth graders connect the history of geometry to problem solving. In this geometry lesson, 10th graders investigate polygons through hands on manipulatives and solve problems relating to parallelograms and triangles. They calculate the...
Curated OER
Angles of a Triangle
Learners explore the measures of the angles of a triangle in this geometry lesson. They use Cabri Jr. to investigate the sum of the measures of the interior angles of a triangle, and examine the relationships between the interior and...
Curated OER
Properties of the Centers of a Triangle
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.