Geometry surrounds us everywhere. Patterns in geometry are used in science, art, construction, architecture, city street planning, home building, interior design, piloting, gardening, and traffic signs. Artists, builders, designers, masons, machinists, and writers all use geometry on the job. Geometry is rich in concepts, problem-solving experiences, and applications. Geometry is important for reasoning and developing skills in forming convincing arguments and proofs.

In this interdisciplinary unit the basics and applications of geometry are presented and reinforced through a multitude of interactive links appealing to adolescents. The primary purpose of the unit is to provide the opportunity for middle school students (grades 6-8) to have fun learning geometry by giving them easy to understand activities to explore.

In the late 1950's in the Netherlands, two mathematics teachers, Pierre and Dieke van Hiele, put forth a theory of development in geometry based on their own teaching and research. They observed that in learning geometry, students seem to progress through a sequence of five reasoning levels, from holistic thinking to analytical thinking to rigorous abstract mathematical deduction. At Level 0, reasoning is visual or holistic, with no particular significance attached to attributes of shapes; hands-on materials are essential. At Level 1, students analytically focus on shapes and can list many of the relevant properties. Abstraction and ordering of properties occur at Level 2; properties and their relationships become the focus. Not until Level 3 are students able to use more formal mathematical deductions, or proofs. (Musser & Berger, 1997, p.507)

The material in this unit is organized according to the van Hiele theory, with emphasis given to the first through third levels of reasoning. This student-centered unit is designed to reinforce the learner's understanding of geometry through creative, interactive, engaging activities. The students practice and apply (new) concepts at their own pace of learning. The activities provide immediate feedback which creates a learning environment where the students can assess their own progress.