Looking for a strategy to organize the information related to transformations? The materials ask pupils to identify a sequence of rigid transformations, identify corresponding angles and sides, and write a congruence statement. They...

Explore angle relationships created by parallel lines and transversals. The 13th lesson of 18 prompts scholars use transparency paper to discover angle relationships related to transversals. Learners find out that these angles pairs are...

Pupils explore the concept of angles and transversals. They construct parallel and non-parallel lines cut by a transversal using Cabri Jr. Learners then determine which angles are congruent and the relationship of angles when two lines...

Build confidence in proofs by proving a known property. Pupils explore two approaches to proving base angles of isosceles triangles are congruent: transformations and SAS. They then apply their understanding of the proof to more complex...

Here is a lesson that has learners take a look at corresponding parts of similar triangles, ratios of similarity, reductions and enlargements. They'll manipulate the scale factor (r) to observe the changes in similar triangles and then...

Assist your class with each angle of geometry as they use exterior angles to form linear pairs with adjacent interior angles. They cover multiple vocabulary terms and work practice problems, complete with justifications, before...

Prove the Angle Sum Theorem of a triangle using parallel line and transversal angle relationships. Pupils create a triangle from parallel lines and transversals. They find angle measures to show that the angles of a triangle must total...

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...

Students identify triangles as similar or congruent. In this geometry activity, students drag triangles around on the navigator to see the effect of different angles on the shape of the triangle. They discuss angle similarity and angle...

Students differentiate between corresponding sides ad angles of two triangles. In this geometry instructional activity, students identify the differences as well as the similarities between two triangles. They differentiate between...

Tenth graders explore congruent triangles.  In this geometry lesson, 10th graders investigate the conditions necessary to prove two triangles congruent.  The lesson combines dry erase board activities and the use of technology.

How similar do figures have to be to be similar figures? Individuals learn to identify similar figures by verifying that angles are congruent and sides are proportional. Additionally, they match the corresponding parts of similar figures.

Who has the best street smarts? An educational lesson has future mathematicians analyze street maps and measure angles on the map to determine if streets are parallel. They also consider safety issues at different types of intersections.

Use the parallel lines to find your way. After first reviewing geometric constructions and the relationships between angles formed by parallel lines and a transversal, young mathematicians write proofs for theorems relating to parallel...

Students calculate the measurement of a central angle. In this geometry lesson, students identify properties of circles. They use Cabri software to create and analyze graphs.

To better understand that the intersection point of two lines lies inside a circle, learners use their keen measurement skills. They discuss arcs, rays, tangent lines, and reflex angles. Then, they put their skills to work as they...

Learners identify different angle pairs. In this geometry lesson, students identify the different angles of two parallel lines cut by a transversal. They identify the interior and exterior angles.

Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...

Students define keywords that are important to solve problems. In this geometry instructional activity, students find the arc length and angle of a circle. They convert between radians and degrees.

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

Students use Geometer's Sketchpad to draw triangles and explore the classificaiton of each using the mearsures of interior angles and the lengths of the sides.

Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice...

How many different types of triangles can your class name? A discovery lesson guides learners through an exploration of the different triangle types and the relationships between their angles and sides. Using coordinate geometry,...

Your learners combine their knowledge of real and imaginary numbers and matrices in an activity containing thirty lessons, two assessments (mid-module and end module), and their corresponding rubrics. Centered on complex numbers and...