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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...
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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...
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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...
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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...
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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 activity provides an...
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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...
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Investigating Area Relationships
Learners investigate the area of various figures. They construct triangles and quadrilaterals using Cabri Jr. and discuss the relationships between different angles, side lengths, and figures.
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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...
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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.
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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.
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Similar Triangles and Proportions
Pupils investigate similar triangles and proportions as they make conjectures about the length of sides of similar triangles. For this lesson, have your class construct similar triangles using Cabri Jr so that they share a common vertex.
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Construction Circles
Pupils investigate the number of points needed to determine a unique circle in a plane. Using Cabri Jr., they apply construction techniques to generate a circle that passes through a given number of points.
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Constructing Quadrilaterals
High schoolers investigate quadrilateral construction in this geometry lesson. They use Cabri Jr. to construct the different quadrilaterals from the quadrilateral hierarchy given minimal definitions. The lesson reinforces the difference...
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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.
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Shortest Distance Between Points and Lines
Learners use technology to determine the shortest between two points in a plane. They are required to support their analytic explanations with visual illustrations.
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Angle Bisectors and Medians of Quadrilaterals
Young scholars investigate the properties of quadrilaterals formed by angle bisectors of a given quadrilateral and quadrilaterals formed by the medians of quadrilaterals. This Cabri Jr. lesson provides opportunity for conjecture and...
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NUMB3RS Activity: Regular Ploygon Centroids
Students investigate geo-profiling. In this secondary mathematics activity, students use geo-profiling to determine the most probable location of a criminal. Students find the centroid of a polygon where the vertices...
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Incenter of a Triangle
Tenth graders explore the properties of the incenter of a triangle. In this geometry lesson, 10th graders construct a triangle and the angle bisectors of each angle. The dynamic properties of Cabri Jr. allow students to locate and...
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NUMB3RS Activity: A Matter of Half-Life and Death
Students investigate exponential decay. Students explore the biological half-life of Cesium-137. Students investigate the Goiania Accident of 1987 which is considered one of the worst incidents in the history of the Atomic...
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Populations Lab - Cultures Lesson: Statistics / Sampling Patterns
Ninth graders examine the application of statistical sampling, data collection, analysis, and representation that exists in schooling and teenage lifestyles in Japan and the United States.
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Skate Party
Learners use the Frayer model during problem solving. In this problem solving lesson, they examine multiple methods of data collection to solve real world problems. Resources are provided.
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Famous Public Properties
What can a middle schooler do in 90 minutes? He can practice using the commutative, associative and distributive properties of addition and multiplication. He can also simplify expressions using the commutative, associative and...
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Will the Leaning Tower Fall?
High schoolers research the Tower of Pisa and write a report about its history. They examine the physics of why it leans and whether it might fall. Students plan a trip to Italy to view the Tower. They develop an itinerary and budget for...
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EasyData Reference
Learners explore the EasyData. In this secondary mathematics lesson plan, students investigate the screens, menus, and list of types of data collection available with the EasyData.