Why spend time listing properties/theorems on the board when your students can be actively engaged in the discovery of such properties. This activity will make use of the TI-Nspire and the TI-Nspire Navigator to exchange files with the students handhelds. The Class Analysis feature of the TI-Nspire Navigator can be used with the use of an LCD projector to display the results of the students' findings to the class.
Before the Activity
Students: Should have prior use of the TI-Nspire. Points that are "draggable" by the student are indicated on the document(s) as open circles.
Teachers: This lesson can be approached from a number of different ways. I have found it useful to use cooperative learning and peer teaching when covering parallelograms, rectangles, rhombuses, and squares. I usually follow this up with a separate, shorter lesson covering the properties of trapezoids, isosceles trapezoids, and kites at the same time.
(This is similar to how the material is presented in many Geometry textbooks)
During the Activity
The teacher will use TI-Nspire Navigator to send the attached 7 TNS files to the students' calculators. The students can be grouped for cooperative learning for this activity.
Each student or group of students will be responsible for their own quadrilateral. They will use the attached Word document to check off or cross off which properties their quadrilateral possesses.
Once this is done, the teacher will collect the students' work, again using the TI-Nspire Navigator. The students' responses can be shown anonymously using Class Analysis and the correct properties will be highlighted in green. This process reports their findings and subsequently presents the properties of each quadrilateral to the other groups (thus filling in the rest of their chart).
If needed, the students can be chosen from their seats using the TI-Nspire Navigator "Make Presenter" option for a student to volunteer how they arrived at their properties.
After the Activity
Answer keys for the properties charts are provided. One key is complete, and one key includes the properties of the parallelograms (and special case parallelograms) to be used in independent lessons, if necessary.
After the students have discovered these quadrilateral properties, time should be spent showing them how to apply these properties to solve for variables and find missing values. Teachers may use their normal textbook and/or worksheet assignments for this task.