Interactive
CK-12 Foundation

Points that Partition Line Segments: Cutting a Log

For Students 9th - 12th
Teach ratios of line segments using an interactive approach. Scholars examine a line segment in the shape of a log and use their knowledge of ratios to divide it into various partitions. As an introductory lesson, the segment has a...
Lesson Plan
EngageNY

Segments That Meet at Right Angles

For Teachers 9th - 12th Standards
Can segments be considered perpendicular if they don't intersect? Learners look at nonintersecting segments on the coordinate plane and make conclusions about the lines that contain those segments. They determine if they are...
Lesson Plan
Curated OER

Lines, Rays, Line Segments, and Planes

For Teachers 6th - 9th
Students are introduced to lines, rays, line segments and planes. They explore the differences between lines, rays, line segments and planes. Students pracice graphing lines, rays, line segments and planes.
Interactive
CK-12 Foundation

Distance Between Two Points: Segment Addition

For Students 9th - 12th Standards
Examine the segment addition postulate through an online simulation activity. An interactive lesson allows scholars to manipulate points and watch as the lengths of segments change. Through their study, they are able to apply the Segment...
Lesson Plan
Curated OER

Dividing Line Segments into n Congruent Parts

For Teachers 9th - 10th
Students identify lines, and line segments. In this geometry lesson plan, students divide line segments into equal congruent parts. They complete a laboratory activity dealing with lines and segments.
Lesson Plan
Curated OER

Geometry is Fun and EverywhereGeometry, You Don’t Care? Geometry is Fun and Everywhere

For Teachers 3rd
Third graders investigate shapes in our world. In this geometry lesson, 3rd graders describe plane and solid shapes and identify angles, solid objects and lines of symmetry. Students use online resources, graphic organizers and conduct...
Lesson Plan
EngageNY

Equations for Tangent Lines to Circles

For Teachers 9th - 12th Standards
Don't go off on a tangent while writing equations of tangent lines! Scholars determine the equations for tangent lines to circles. They attempt both concrete and abstract examples, such as a tangent line to the unit circle through...
Interactive
CK-12 Foundation

Bisectors of Line Segments and Angles: Cut a Line

For Students 9th - 12th
Geometric constructions build relationships —by simply manipulating simple tools. An interactive lesson presents a completed construction of a segment bisector and has learners analyze the important aspects. Ultimately, they should be...
Lesson Plan
Curated OER

Perpendicular Bisector of a Line Segment

For Teachers 9th - 12th Standards
High Schoolers investigate the perpendicular bisector of a line segment. They use Cabri Jr. to construct the perpendicular bisector of a segment. The dynamics capabilities of Cabri Jr. allow your learners to observe the lengths of the...
Lesson Plan
Curated OER

Identify Polygons: Algebra/Geometry Institute

For Teachers 8th
Eighth graders classify geometric figures.  In this polygon lesson, 8th graders identify given geometric figures.  They compare and contrast different polygons.  Students name line segments, identify parallel lines, and...
Lesson Plan
PBS

Plotting Pairs of Coordinate Points in All Four Quadrants to Construct Lines

For Teachers 5th - 8th Standards
Your young graphers are motivated by watching three Cyberchase videos to plot points in all four quadrants, connect pairs of points to make a line segment, and find the point of intersection of two lines.
Lesson Plan
Curated OER

Segment and Distance

For Teachers 7th - 10th
Learners explore the definitions of segment and distance. They perform hands-on activities to form a segment and examine distance. Following teacher guidance, they construct congruent line segments. Independently, they find the...
Lesson Plan
Curated OER

Investigating Segments in a Triangle

For Teachers 9th - 12th Standards
Pupils investigate segments in a triangle by constructing a triangle using Cabri Jr. They construct segments within the triangle that lie on the midpoints of the triangle's sides. Learners then compare the slope of base of the triangle...
Lesson Plan
Curated OER

Sample Lesson Plan on Lines and Angles

For Teachers 3rd - 5th
Student complete worksheet using the definitions of lines and angle vocabulary. They define the word and follow a direction given on the worksheet such "construct a line." They complete an online tutorial on how to measure angles using a...
Lesson Plan
EngageNY

Parallel and Perpendicular Lines

For Students 9th - 12th Standards
Use what you know about parallel and perpendicular lines to write equations! Learners take an equation of a line and write an equation of a line that is parallel or perpendicular using slope criteria. They then solve problems to...
Lesson Plan
EngageNY

The Distance from a Point to a Line

For Students 9th - 12th Standards
What is the fastest way to get from point A to line l? A straight perpendicular line! Learners use what they have learned in the previous lessons in this series and develop a formula for finding the shortest distance from...
Lesson Plan
EngageNY

Lines That Pass Through Regions

For Students 9th - 12th Standards
Good things happen when algebra and geometry get together! Continue the exploration of coordinate geometry in the third lesson in the series. Pupils explore linear equations and describe the points of intersection with a given polygon as...
Interactive
CK-12 Foundation

Midpoint and Segment Bisectors: Midpoint Map

For Students 9th - 12th Standards
Discover how to find a midpoint with a conceptual exploration. Scholars manipulate a point to determine the location of a midpoint on a straight line distance between two locations. Later questions extend to determine the...
Lesson Plan
Texas Instruments

Points, Lines, and Planes

For Teachers 9th - 12th Standards
Students solve problems dealing with points, lines and planes. In this geometry lesson, students differentiate between parallel lines and planes. They find the intersection of lines and planes.
Interactive
CK-12 Foundation

Bisectors of Line Segments and Angles: Cut an Angle

For Students 6th - 10th
Explore constructions through an interactive online lesson. Given an example of an angle bisector construction, learners investigate the markings to determine the method used. Challenge questions help solidify the steps. 
Lesson Plan
Texas Instruments

Investigating Segments in a Quadrilateral

For Teachers 9th - 12th Standards
Investigate the properties of the shape formed by connecting the midpoints of adjacent sides of a quadrilateral. In this properties of the shape formed by connecting the midpoints of adjacent sides of a quadrilateral lesson, high...
Lesson Plan
EngageNY

Criterion for Perpendicularity

For Students 9th - 12th Standards
The Pythagorean Theorem is a geometry pupil's best friend! Learners explain the equation a1b1 + a2b2 = 0 for perpendicular segments using the Pythagorean Theorem. They are able to identify perpendicular segments using their...
Lesson Plan
EngageNY

Special Lines in Triangles (part 1)

For Students 9th - 10th Standards
Allow your pupils to become the mathematicians! Individuals explore the properties of a midsegment of a triangle through construction and measurement. Once they figure out the properties, learners use them to draw conclusions.
Interactive
CK-12 Foundation

Distance Between Two Points: Taxicab Distance

For Students 8th - 10th Standards
Apply geometry to find the distance as the crow flies. An engaging lesson compares the distance a car must drive to the straight line distance between two locations. Scholars must manipulate a simulation, note the change in distances,...