CK-12 Foundation
Ck 12: Geometry: Perpendicular Lines in the Coordinate Plane
[Free Registration/Login may be required to access all resource tools.] Use slopes to determine if two lines are perpendicular.
CK-12 Foundation
Ck 12: Geometry: Parallel Lines in the Coordinate Plane
[Free Registration/Login may be required to access all resource tools.] Use slopes to determine if two lines are parallel.
Oswego City School District
Regents Exam Prep Center: Intuitive Notion of Line Symmetry and Plane Symmetry
Definitions are provided line of symmetry, line symmetry, and plane symmetry, and several nice examples are provided that illustrate these definitions.
CK-12 Foundation
Ck 12: Geometry: Slope in the Coordinate Plane
[Free Registration/Login may be required to access all resource tools.] This concept reviews how to calculate the slope of a line given two points on the line.
CK-12 Foundation
Ck 12: Geometry: Parallel and Perpendicular Lines
[Free Registration/Login may be required to access all resource tools.] Identify intersecting, parallel and perpendicular lines in a plane
Math Planet
Math Planet: Pre Algebra: Geometry Fundamental Statements
Provides examples and a video lesson that introduce fundamental statements of geometry.
PBS
Pbs Learning Media: Two Points Determine a Line
In this video segment [2:10] from Cyberchase, Digit must make a straight line between the two points and then follow the path created.
CK-12 Foundation
Ck 12: Geometry: Perpendicular Lines
[Free Registration/Login may be required to access all resource tools.] This concept teaches students about perpendicular lines.
CK-12 Foundation
Ck 12: Parallel Lines
[Free Registration/Login Required] Students explore the concept of parallel lines by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about the...
CK-12 Foundation
Ck 12: Elem Math: Identifying Straight Lines in Various Shapes
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on determining if there are straight lines in various two dimensional shapes.
Oswego City School District
Regents Exam Prep Center: Length of a Line Segment (Distance)
Use the coordinate plane and Pythagorean theorem to determine the length of a line segment. Click on the "Topic Index" to find a related practice exercise and teacher resource.
CK-12 Foundation
Ck 12: Geometry: Basic Geometric Definitions
[Free Registration/Login may be required to access all resource tools.] In this lesson students identify points, rays, lines, and line segments. Students examine guided notes, review guided practice, watch instructional videos and...
Shodor Education Foundation
Shodor Interactivate: Lesson: Lines, Rays, Line Segments, & Planes
This robust lesson plan for upper elementary and middle school grades introduces the concepts for lines, rays, line segments, and planes. Resources are linked to it and ready for your use.
Illustrative Mathematics
Illustrative Mathematics: G Co Defining Parallel Lines
Alex and his friends are studying for a geometry test and one of the main topics covered is parallel lines. They each write down what they think it means for two distinct lines in a plane to be parallel. Students are asked to analyze...
CK-12 Foundation
Ck 12: Elem Math: Counting Straight Lines and Curves in Various Shapes
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on counting lines and curves in various two dimensional shapes.
ClassFlow
Class Flow: Basic Geometry Vocabulary
[Free Registration/Login Required] This flipchart is an introduction to geometry vocabulary and elementary geometric figures. Activities ask students to match vocabulary and definitions and label figures. Assessment questions follow.
Integrated Publishing
Plane Figures
This site describes lines and angles "as found in various plane (flat) geometric figures.".
The Math League
The Math League: Basic Terms: Parallel Lines
This tutorial provides an explanation and example of parallel lines.
Math Planet
Math Planet: Geometry: Measure Line Segments
Explores how to measure the length of a line segment through examples and a video lesson. [0:40]
Math Planet
Math Planet: Geometry: Measure and Classify an Angle
Explains the terms and symbols used to discuss line angles, what an angle is, and the types of angles. Includes short video lesson demonstrating how to use a protractor to measure an angle. [0:57]
Oswego City School District
Regents Exam Prep Center: Intuitive Symmetry: Point, Line, Plane, Rotational
Investigate the concept of symmetry at this test prep site. See detailed definitions and picture examples, answer the questions in the interactive practice pages, and do the classroom activity where students use a digital camera to...
ClassFlow
Class Flow: Introduction to Geometry
[Free Registration/Login Required] This flipchart is a basic introduction to Geometry: points, lines and planes. The flipchart contains movable objects (with an emphasis on student participation) and Activotes.
CK-12 Foundation
Ck 12: Geometry: Slope in the Coordinate Plane
[Free Registration/Login may be required to access all resource tools.] Find the slope of a line given two points. Includes a video [5 min. 29 sec.], examples, and review problems along with an answer key.
CK-12 Foundation
Ck 12: Geometry: Segments From Secants and Tangents
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to solve for missing segments created by a tangent line and a secant line intersecting outside a circle.