Activity Overview
In this activity, students use the tools of Cabri™ Jr to test their knowledge of geometry. They investigate the properties of the shape formed by connecting the midpoints of adjacent sides of a quadrilateral. NCTM Geometry Standard covered: Analyze characteristics and properties of 2- and 3-dimensional geometric shapes and develop mathematical arguments about geometric relationships.
Before the Activity
Install the Cabri Jr. App on the students' graphing calculators using TI Connect™, a TI Connectivity Cable, and the Unit-to-Unit Link Cable
See the attached PDF file for detailed instructions for this activity
Print pages 34 - 35 from the attached PDF file for your class
During the Activity
Distribute the pages to your class.
Follow the Activity procedures:
Draw a quadrilateral
Find the midpoints of the sides of the quadrilateral
Draw segments to join the midpoints of adjacent sides of the quadrilateral
Explore characteristics of the shape formed
Show that one pair of opposite sides is parallel and congruent
Test this conjecture on other quadrilaterals by moving to a vertex
After the Activity
Review student results:
As a class, discuss questions that appeared to be more challenging
Re-teach concepts as necessary