Can you prove it? Making assumptions in geometry is commonplace. This resource requires mathematicians to prove the parallel line postulate through constructions. Learners construct parallel lines with a 180-degree rotation and then...

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...

Streets, bridges, and intersections, oh my! Parallel lines and transversals are a present in the world around us. Learners begin by discovering the relationship of the angles formed by parallel lines and a transversal. They then...

Young scholars explore the concept of angles formed by parallel lines.They graph two parallel lines cut by a transversal, then measure the angles formed by the transversal and record the data in a table. Learners make conjectures about...

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...

We can mathematically model the path of a robot. Learners use parametric equations to find the location of a robot at a given time. They compare the paths of multiple robots looking for parallel and perpendicular relationships and...

This one activity requires young geometers to pull together information they are currently learning with things they have learned previously. Here they rely on understanding something about parallel lines, alternative interior angles,...

Have your class create parallel lines. Young scholars will learn how to identify the different angles created by a parallel line cut by a transversal. Then, they identify and name similar and different angles.

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....

Students investigate the relationship between perpendicular and parallel lines on a coordinate plane. In this geometry activity, students differentiate lines based on their slopes.

Young scholars 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.

Students differentiate between parallel and perpendicular lines. In this geometry lesson, students make conjectures and apply it to solve real life situations. They collect data and make predictions based on the data.

How many ways can you create a dilation? Many! Individuals strengthen their understanding of dilations by using various methods to create them. The new technique builds on pupils' understanding of the ratio method. Using the ratio,...

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...

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...

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...

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.

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.

Students calculate the slope of parallel and perpendicular lines.In this algebra lesson, students differentiate between parallel and perpendicular lines. They graph their lines using the slope of the equation.

Learn through constructions! Learners examine a translation using constructions and define the translation using a vector. Pupils then construct parallel lines to determine the location of a translated image and use the vector as a guide.

Tenth graders investigate parallel lines and their special angles cut by a transversal. In this geometry lesson, 10th graders identify and find corresponding, alternate interior, and alternate exterior angles formed when parallel lines...

Students find the slopes for perpendicular and parallel lines. In this geometry lesson, students differentiate between parallel and perpendicular lines. They use Cabri software to create lines to compare.

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...

High schoolers calculate the distance between two points. In this geometry lesson plan, students define the meaning of the distance between parallel lines. They find the point of intersection of other lines.