Curated OER
Altitude, Median, and Angle Bisector of a Triangle
Learners investigate the special properties of an altitude, a median, and an angle bisector and explore how these special segments divide the area of a triangle. The dynamic nature of Cabri Jr. allows pupils to form and verify conjectures.
Curated OER
Archeologist Frieze Patterns
Learners construct frieze patterns using translations and rotations. They will discuss how frieze patterns are similar to jigsaw puzzles and use Cabri Jr. to build a triangle frieze pattern using rotations, translations, and reflections.
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
Exploring the Centroid of a Triangle
Pupils examine the centroid of a triangle as they use Cabri Jr. to construct a triangle and its medians. The dynamic nature of the software allows learners to measure the lengths of the segments in the triangle and conjecture and verify...
Curated OER
What's the Spin?
Learners use the CABRI application for their graphing calculator to rotate, translate, and reflect triangles. They use graphing calculators and follow detailed directions to manipulate triangles in specified ways. There are three...
Curated OER
Investigating Segments in a Triangle
Pupils investigate segments in a triangle by constructing a triangle using Cabri Jr. They construct segments within the triangle that lie on the midpoints of the triangle's sides. Learners then compare the slope of base of the triangle...
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
Investigating Segments in a Right Triangle
High schoolers explore the concept of right triangles as they construct a right triangle using Cabri Jr. Learners find the midpoint of the hypotenuse and construct a line from the midpoint to the vertex of the right angle. They then...
Curated OER
Investigating Lengths of Segments in a Triangle
Pupils explore the midsegment of a triangle in the geometry lesson. They draw and measure the segment joining the midpoints of the two sides of a triangle and compare its length to the length of the third side of the triangle. The...
Curated OER
Reflections in the Plane
Have your class explore the concept of reflections as they use Cabri Jr. to construct a triangle and reflect it over a line. Learners reflect shapes across the coordinate plane and across the lines y = x and y = -x.
Curated OER
Measuring Angles in a Triangle
High schoolers investigate the sum of the measures of the angles of a triangle. They draw a triangle and measure the interior angles. Using Cabri Jr., learners find the sum of the measures of the interior angles. The lesson provides an...
Curated OER
Exploring the Orthocenter of a Triangle
Young mathematicians explore the concept of triangles as they construct altitudes of triangles to find the orthocenter. Learners construct their triangles using Cabri Jr. on their graphing calculators and find that the altitudes of a...
Curated OER
Constructions Triangles
Learners explore the difference between a construction and a drawing. They focus on various ways to construct different types of triangles. The lesson is an application of Cabri Jr. and reinforces the difference between a constructions...
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.
Curated OER
Triangle Inequality Theorem
High schoolers investigate the relationship between angle measures and sides of a triangle and the relationships among the three sides of a triangle. The use of technology (Cabri, Jr.) allows learners to make and test conjectures as they...
Curated OER
Midsegments of a Triangle
Students analyze midsegments of triangles in this instructional activity. They use Cabri Jr. software to observe the relationships between interior angles and midsegments of triangles. Specific instructions for creating this...
Curated OER
Ratios in Right Triangles
Learners calculate the sides of right triangles in this trigonometric ratios lesson. They use Cabri Jr. software and TI-83 or TI-84 calculators to find the side lengths and their ratios to each other for various triangles. The provided...
Curated OER
Rotations in the Plane
Pupils investigate the properties of a rotation as they use technology (Cabri, Jr.) to observe the relationship between the pre-image and the image formed by the rotation. The lesson provides ample opportunity for learners to conjecture...
Curated OER
Connecting Translations, Reflections, and Rotations
Learners differentiate between translation, reflection and rotation. They explore the 3 types of transformation using Cabri Jr. and build on previous knowledge in this lesson.
Curated OER
Handy Reflections
Learners explore reflections on a coordinate plane in this lesson. They trace their hand on a grid, determine the coordinates of each point, and create a scatter plot of their points. Pupils use this information to investigate aspect...
Texas Instruments
Golden Ratio Lab
Learners investigate the Golden Ratio in this algebra I or geometry instructional activity. They explore the Golden Ratio as the conduct an experiment in which they collect various measurement from their team members and find the...
Curated OER
Cabri Jr. - Getting Started with Triangles
Students explore a basic triangle construction. In this beginning geometry instructional activity, students investigate the steps to necessary to create an equilateral triangle with Cabri Jr.;
That Quiz
That Quiz: Practice Test: Geometry
This resource allows users to test their geometry knowledge.
Texas Instruments
Texas Instruments: Investigating Properties of Kites
In this activity, students construct kites and investigate their properties. They also relate the properties to squares and rhombi.