EngageNY
Angles Associated with Parallel Lines
Explore angle relationships created by parallel lines and transversals. The 13th lesson plan of 18 prompts scholars use transparency paper to discover angle relationships related to transversals. Learners find out that these angles pairs...
Curated OER
Constructing Parallel Lines
Students construct parallel lines using a protractor and a straightedge. In this geometry lesson, students identify the properties of parallel lines. They use Cabri to graph and observe the lines.
Curated OER
Parallel and Perpendicular Lines
Tenth graders explore parallel and perpendicular lines. In this geometry lesson, 10th graders investigate the relationships associated with parallel lines and transversals, perpendicular lines, and the angles formed by these...
Curated OER
Lines, Lines, Everywhere
Pupils explore linear equation suing real life scenarios. In this algebra lesson, students find the slope and intercept of a line. They create table of values to plot their graph and draw conclusions.
EngageNY
Unknown Angle Proofs—Proofs of Known Facts
Lead the class in a Greek history lesson with a geometric twist. Pupils relate a short video about geometric properties to modern-day methods of solving for unknown angles. They discuss parallel line theorems and complete...
Curated OER
Making Parallel Lines
Students differentiate between parallel and perpendicular lines. In this geometry instructional activity, students make conjectures and apply it to solve real life situations. They collect data and make predictions based on the data.
Alabama Learning Exchange
Mirror, Mirror on the Wall: Reflections of Light
Why can we see our reflection in a window but not a brick wall? Young physicists learn the Law of Reflection and various light properties that help them answer this and other questions about reflection. Use the PowerPoint to introduce...
Mathematics Vision Project
Similarity and Right Triangle Trigonometry
Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...
EngageNY
Definition of Reflection and Basic Properties
Discover the results of reflecting an image. Learners use transparency paper to manipulate an image using a reflection in this fourth lesson plan of 18. They finish by reflecting various images across both vertical and horizontal lines.
EngageNY
Special Lines in Triangles (part 1)
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.
Key Curriculum Press
Properties of Special Parallelograms
Rhombuses, rectangles and squares are have special properties. In this activity, young geometers investigate and make conjectures about diagonals, angles, and parallel lines of parallelograms.
Curated OER
Investigating the Slopes of Parallel and Perpendicular Lines
High schoolers investigate parallel and perpendicular lines. They use Cabri Jr. to construct and explore the relationships between the slopes of parallel and perpendicular lines. The drawing and measurement tools available with Cabri Jr....
Curated OER
Parallel-o-Home
Students investigate the usage of parallel and perpendicular shapes in the real world. In this geometry lesson, students investigate shapes for properties that are related to the real world. They relate all the properties of shape tot he...
Curated OER
Properties of Special Quadrilaterals
Teach your mathematicians how to identify the properties of quadrilaterals. In this geometry lesson plan, students solve for missing angles and sides of a special quadrilateral. They use the TI to move the sides around and create...
EngageNY
Special Lines in Triangles (part 2)
Medians, midsegments, altitudes, oh my! Pupils study the properties of the median of a triangle, initially examining a proof utilizing midsegments to determine the length ratio of a median. They then use the information to find missing...
Illustrative Mathematics
Dilating a Line
High School geometers verify through experimentation certain properties about dilations. This multi-step problem challenges them to construct examples of dilations to verify specific facts, the final step provides an opportunity to more...
Illustrative Mathematics
What Shape Am I?
Sharpen your pencil and grab a ruler, it's time to draw some quadrilaterals! Given the definition of a parallelogram, rectangle, and rhombus, learners draw examples and nonexamples of each figure. The three definitions are...
Curated OER
Properties of Special Parallelograms
Students identify properties of trapezoids. In this geometry lesson, students are put into groups and use computer programs to analyze polygons. They drag and move the shapes around as they make predictions.
EngageNY
Definition of Rotation and Basic Properties
Examine the process of rotating images to visualize effects of changes to them. The fifth instructional activity of 18 prompts pupils to rotate different images to various degrees of rotation. It pays special attention to rotations in...
Curated OER
Angle Action 1,2 and 3
Students investigate angles through construction. In this geometry instructional activity, students use a protractor to identify the measurement of an angle. They identify angles cut by a transversal and two parallel lines.
Ohio Department of Education
I Can Name that Angle in One Measure! - Grade Eight
Collaborative groups work with geometry manipulatives to investigate conjectures about angles. They create a graphic organizer to use in summarizing relationships among angles in intersecting, perpendicular and parallel lines cut by a...
Curated OER
Constructing Perpendicular Bisectors
Tenth graders investigate parallel lines and the angles formed when cut by a transversal. In this geometry lesson, 10th graders construct perpendicular lines and discuss midpoint, segments and perpendicular bisectors. They relate...
EngageNY
Congruence, Proof, and Constructions
This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs. Each of the almost-forty lessons...
Curated OER
Exploring Properties of Rectangular Prisms
Students explore the properties of rectangular prisms. For this geometry lesson, students identify properties of two and three dimensional shapes. They use Cabri technology to create polygons and solve problems.