We present an investigative activity that was set as part of a course of pre-service teachers of mathematics. The emphasis in the course was set on the importance of using the computerized technological tool for teaching the subject. The activity focused on investigating interesting geometrical conservation properties which are not known to the…

We present a geometrical investigation of the process of creating an infinite sequence of triangles inscribed in a circle, whose areas, perimeters and lengths of radii of the inscribed circles tend to a limit in a monotonous manner. First, using geometrical software, we investigate four theorems that represent interesting geometrical properties,…

The use of the dynamic mathematics software GeoGebra to solve geometric problems on conics and loci from an 18th century textbook will be presented. In particular, examples will be shown of how the use of this program helped the authors to understand the method that our predecessors used to deal with conic sections together with solving loci…

In this article, we present investigative tasks that concern loci, which integrate the use of dynamic geometry software (DGS) with mathematics for proving the obtained figures. Additional conditions were added to the loci: ellipse, parabola and circle, which result in the emergence of new loci, similar in form to the original loci. The…

The complementary use of the theories of instrumental genesis and shifts of attention enabled me to obtain insights into students' understandings of the concepts of eigenvector and eigenvalue. My analysis suggests that the use of different dragging modalities can provide evidence of shifts in structure of a student's attention and consequently can…

This study focuses on mathematics teachers' professional development through elements of Japanese lesson study. The teachers designed a research lesson with regard to sense-making of the derivative using the integration of GeoGebra. In the second year of the four-year lesson study project, seven secondary school teachers--from different Dutch…

In this article, the authors describe a free interactive circular geoboard environment that can lead learners to pose mathematical questions. They list three major ways in which one can imagine the environment and problems being used by teachers. Among other things, they discuss how the environment could support teaching and learning, and how the…

Outlines a geometry task that uses computers to transform some quadrilaterals into other quadrilaterals. (ASK)

The title may appear daunting, but the exercises, which can be presented to students from middle school to graduate school, are not. The exercises center on creating fractal images in the xy-plane with free. easy-to-use software and questions appropriate to the level of the student.

Steiner's Porism states that if you can draw a connected ring of circles in the annular region between two original circles, the ring will be successfully completed no matter where you start. This paper explores how the TI-92 graphing calculator can be used to demonstrate Steiner's Porism and illustrate the main points of its proof. Inversion in…

This paper introduces a teaching unit on using spiral symmetry in a geometry course for secondary education majors. The TI-92 graphing calculator is used to exploit the exponential function to analyze the geometric topic of similarity and to study the derivative of spirals. The paper provides some procedures and programs to generate spirals using…

Explores useful ways of teaching the volume of pyramids using cubic blocks and spreadsheets. Presents a lesson plan with teaching suggestions. (KHR)

Describes PC Logo, an instructional tool that can be used for teaching and enhancing a student's knowledge of graphs and geometric concepts. (CCM)

Extends a counting activity described in the April 1997 issue of "The Mathematics Teacher" entitled, "The Pyramid Question: A Problem Solving Adventure." In this activity, students must find all triangles with positive integral sides and a perimeter of 36. Considers triangles with perimeters other than 36 for this activity and…

Describes the maximum-volume-box problem designed to lead students to a deeper understanding of the problem and its solution. Uses the Geometer's Sketchpad as a learning tool. Illustrates some examples of constructing and using the sketch. (KHR)