Worksheets on constructing the circumcenter, the centroid, the orthocenter, the incenter, and the Nine-Point Circle in a triangle are provided for duplication. (DT)

The activities are designed to have students manipulate physical models of geometric figures, engage in spatial visualization and observe relationships between triangles and parallelograms and between triangles and rectangles. Worksheets designed for duplication are included in the materials and an answer key is provided. (MP)

Three worksheets are provided to help secondary students explore relationships among the areas of a variety of similar figures constructed on the sides of right triangles. The activity is extended to include the relationship among the lengths of the sides of the right triangle. Included are several student worksheets. (DC)

This is one of a series of geometry modules developed for use by secondary students in a laboratory setting. This module, intended to present a treatment of congruent triangles which is not totally axiomatic, contains six sections: (1) Draw vs. Construct; (2) Triangle Construction; (3) Arguing for Congruence; (4) Parallel Line Construction; (5)…

This is one of a series of geometry modules developed for use by secondary students in a laboratory setting. The purpose of this module is to teach solution of proportions, concepts and theorems of triangle similarity, solution of the Pythagorean Theorem, solution of the isosceles right triangle, and concepts involving "rep-tile" figures…