TABLE OF CONTENTS

- Spark Notes: Geometric Proofs
- Wikibooks: Mathematical Proofs
- Flow Chart Proofs
- The Proof Process Activities
- Proof in Dynamic Geometry: More than Verification
- G2 Unit Outline
- Geometry Problems: Circles and Triangles
- Inscribing and Circumscribing Right Triangles
- Parallel Lines and Pairs of Angles
- Parallel Lines and Transversals
- Two Lines and a Transversal
- Triangle Sum Theorem Activity 1
- CK12 Triangle Sum Theorem
- CK12 Parallelograms
- ProveIt! Two-Column Proofs Practice Tool
- CK12 Diagrams in Proof
- Meet the Parallelogram: Properties of Paralleograms
- Midsegments
- Practice Isosceles Triangles
- Proving Triangle Theorems
- Medians in a Triangle
- Circumcenter
- Triangle Centers

Online

Spark notes article on geometric proof. For reference use.

Wikibooks article on mathematical proofs. For reference use.

Fill in the blank notes for creating flow proofs

Notes and activity ideas for creating and understanding proofs

Article by Michael de Villiers. For reference use.

Another state's proposed outline for teaching G2.

This lesson unit is intended to help you assess how well students are able to use geometric properties to solve problems. In particular, the lesson will help you identify and help students who have the following difficulties: Solving problems by determining the lengths of the sides in right triangles. Finding the measurements of shapes by decomposing complex shapes into simpler ones. The lesson unit will also help students to recognize that there may be different approaches to geometrical problems, and to understand the relative strengths and weaknesses of those approaches.

This lesson unit is intended to help you assess how well students are able to use geometric properties to solve problems. In particular, it will help you identify and help students who have difficulty: Decomposing complex shapes into simpler ones in order to solve a problem. Bringing together several geometric concepts to solve a problem. Finding the relationship between radii of inscribed and circumscribed circles of right triangles.

Good resource for understanding the special pairs of angles formed by parallel lines and transversals.

This is a link to a section from a textbook (unknown). The section has some problems that could be elaborated on to make better performance tasks from.

This is a lesson starting with the warmup activity and ending with some independent practice. This includes construction activities as well.

From the Engaging Geometry Activites TEKS workbook. Good activity for exploring the Triangle Sum Theorem through parallel lines and transversals and parallelograms.

Several links on this page to readings, videos, and interactive exercises to explore The Triangle Sum Theorem.

CK12 page with various readings, videos, activities, etc. on parallelograms.

Online tool for picking statements and reasons.

This has some information on using diagrams in proof and gets the students a bit more comfortable with implications given information in a diagram.

Students construct a parallelogram, measure the side lengths and angles, and observe that opposite sides are congruent, opposite angles are congruent, and consecutive angles are supplementary. Then they construct the diagonals, measure the distances from the vertices to the point of intersection, and discover that the diagonals bisect each other.

Geometer's Sketchpad sketch that investigates midsegments of triangles.

Online questions about Isosceles Triangles, their angles, and their sides.

Show theorems about triangles are true, such as "measures of interior angles of a triangle sum to 180 degrees", "base angles of isosceles triangles are equal", and more.

Geometer's Sketchpad activity, complete with worksheets, investigating medians of a triangle.

Geometer's Sketchpad sketch on circumcenters.

Website that explores centers of a triangle. It also has links to Geometer's Sketchpad sketches to help explore the concepts further.