National Research Center for Career and Technical Education
Architecture and Construction: Stair Construction
Within the context of the construction industry, algebra pros begin to calculate slope from the sizes of stair steps. This is a terrific lesson, especially for aspiring engineers. Just be aware that it might be a stretch to meet all of...
Curated OER
Inscribing a Square in a Circle
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...
Curated OER
Inscribing a Hexagon in a Circle
This activity is a follow-on activity to inscribing a square in a circle. The overall problem is more complex. It deals with geometric constructions, properties of triangles, and regular hexagons. The final part of the activity finds the...
EngageNY
Construct a Nine-Point Circle
There are an infinite number of points on a circle; can you find nine of them? After putting together a nine-point circle, pupils use constructions and their knowledge of triangle segments to determine the center of the circle. Learners...
National Research Center for Career and Technical Education
Health Science: Back to Basics
This lesson focuses on unit conversion, proportions, ratios, exponents, and the metric system. Discuss measurement with your math class and demonstrate how to solve several health-science word problems. Give learners a chance to visit an...
Curated OER
Properties of Special Quadrilaterals
Teach your mathematicians how to identify the properties of quadrilaterals. For this geometry lesson, students solve for missing angles and sides of a special quadrilateral. They use the TI to move the sides around and create different...
Curated OER
Creating a Cyclic Quadrilateral
Identify and make conjecture about properties of cyclic quadrilaterals. Students use the TI Navigator to create different shapes and draw conclusions.
Texas Instruments
Investigating Segments in a Quadrilateral
Investigate the properties of the shape formed by connecting the midpoints of adjacent sides of a quadrilateral. In this properties of the shape formed by connecting the midpoints of adjacent sides of a quadrilateral lesson, high...
Curated OER
Reflecting a Triangle in the Coordinate Plane
Learners explore geometric concepts using technology. They manipulate the TI to find important math topics. This activity requires a TI-84 or higher.
Curated OER
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...
Texas Instruments
REAL LIFE REAL WORLD Activity - Surveyor
Learners investigate surveying in this secondary mathematics lesson. They will explore a real world application of geometry and trigonometry as they create a plot plan using a geometry utility and calculate the area of the land parcel.
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
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
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.
Curated OER
Circumscribing a Circle About a Triangle
Pupils circumscribe a circle about a triangle. They construct a triangle using Cabri Jr and then circumscribe it. They then use knowledge of perpendicular bisectors and circumcenters to locate the center of the circle and then...
Curated OER
Exploring the Circumcenter of a Triangle
Students construct the circumcenter of a triangle. In this constructing the circumcenter of a triangle lesson, students construct a triangle using Cabri Jr. Students draw perpendicular bisectors of the sides of the triangle. Students...
Curated OER
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.
Curated OER
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...
Curated OER
Measuring Angles in a Quadrilateral
High schoolers explore quadrilaterals in this geometry lesson. They will draw a quadrilateral, measure the angles, and find the sum of the measures of the interior angles using Cabri Jr. The interactive capabilities of Cabri Jr. allow...
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 instructional activity is an application of Cabri Jr. and reinforces the difference between a...
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.