Unit Plan
CK-12 Foundation

Ck 12: Geometry: Alternate Exterior Angles Intermediate

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to alternate exterior angles and how to use them to determine whether or not lines are parallel.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Alternate Interior Angles Intermediate

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to alternate interior angles and how to use them to determine whether or not lines are parallel.
eBook
Math Planet

Math Planet: Pre Algebra: Angles and Parallel Lines

For Students 9th - 10th Standards
Explains angles and parallel lines through examples and a video lesson.
Handout
CK-12 Foundation

Ck 12: Geometry: Angles and Transversals Study Guide

For Students 9th - 10th Standards
This study guide on angles and transversals covers key terms, angle types formed by transversals, postulates and theorems about transversals, and how to prove if lines are parallel or perpendicular. It is available for download with free...
Unit Plan
CK-12 Foundation

Ck 12: Alternate Interior Angles

For Students 9th - 10th
[Free Registration/Login Required] Students explore the concept of alternate interior angles by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more...
Lesson Plan
Shodor Education Foundation

Shodor Interactivate: Lesson: Angles

For Teachers 3rd - 8th Standards
This upper elementary and middle school lesson plan introduces the concept of acute, obtuse and right angles. Also, as the instructional activity proceeds vertical, adjacent, alternate interior and alternate exterior angles are explored....
eBook
CK-12 Foundation

Ck 12: Interactive Geometry: 4.2 Theorems About Lines and Angles

For Students 9th - 10th Standards
Consider two parallel lines that are intersected by a transversal, and when it crosses the two others, many different angle pairs are formed. See the special properties of the angle pairs in this interactive.
Activity
Analyze Math

Analyze Math: Parallel Lines and Angles Problems

For Students 9th - 10th
Try these three problems about finding the measures of different angles that arise from diagrams involving parallel lines and transversals. Detailed solutions are written out for these three problems of moderate difficulty.
Unknown Type
Khan Academy

Khan Academy: Finding Angle Measures Between Intersecting Lines

For Students 7th Standards
Practice finding angle measures between intersecting lines.
Lesson Plan
Alabama Learning Exchange

Alex: Build a City on Geometry

For Teachers 6th - 8th
The students will be split into small, cooperative groups and build a city following specific guidelines. The students will learn how a city is constructed with angles, intersections, parallel, intersecting, and transversal streets. They...
Interactive
Mangahigh

Mangahigh: Shape: Alternate Segment Rule for Circles

For Students 9th - 10th Standards
Use the alternate segment rule for cirlces to determine the angle measures.
Handout
Geometry Help

Geometry Help: What Are Parallel Lines in Geometry?

For Students 9th - 10th Standards
Explains the basic concept of parallel lines in Geometry with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
Whiteboard
ClassFlow

Class Flow: Angles in Geometry

For Teachers 6th - 8th Standards
[Free Registration/Login Required] This flipchart is a look at angles in geometry. Drawing, labeling, measuring, special angles: (right, straight, acute, obtuse) and congruence.
Handout
Sonoma State University

Sonoma State University: Parallel Lines and Similar and Congruent Triangles

For Students 9th - 10th Standards
This site defines parallel lines, parallel lines cut by a transverse, and congruent triangles. It also contains links for related terms.