Radford University
Parallel Lines, Transversals, and Angles: What’s the Connection?
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...
Curated OER
Identifying Linear Functions from Graphs
Keep your mathematicians engaged using this group linear functions activity. Each of ten groups receives two graphs with both an image and equation, as well as a "who has" phrase to call out the next graph. Scholars stay on their toes as...
02 x 02 Worksheets
Slope
What does slope have to do with lines? Pupils work with lines and determine the slope of the lines informally and with the slope formula. Groups use their knowledge to calculate the slopes of parallel and perpendicular lines. They also...
Mathematics Vision Project
Transformations and Symmetry
Flip, turn, and slide about the coordinate plane. Pupils define the rigid motions and experiment with them before determining the relationships of the slopes of parallel and perpendicular lines. The sixth unit in a nine-part series...
Illustrative Mathematics
What is a Trapezoid? (Part 2)
This collaborative activity investigates the meaning of a trapezoid and a parallelogram. It begins by presenting two different definitions of a trapezoid. Learners are to reason abstractly the difference between the two definitions and...
Mathematics Assessment Project
Identifying Similar Triangles
Math whizzes work with angle sums and exterior angles to figure out the measure of other angles. This particular publication provides comprehensive support in the form of an anticipatory activity, questions designed to prompt discussion,...
EngageNY
First Consequences of FTS
Challenge the young mathematicians to find the exact coordinates of a dilated point. The fifth segment in a 16-part series introduces the class to the converse of the Fundamental Theorem of Similarity. Scholars use the theorem to...
EngageNY
Informal Proof of AA Criterion for Similarity
What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply...
EngageNY
Slicing a Rectangular Prism with a Plane
What do you get when you slice a prism? Pupils discover that the answer depends on how the prism is sliced. The second half of the 29-part module focuses on three-dimensional objects. Learners use their two-dimensional vocabulary and...
Geometry Accelerated
Coordinate Geometry Additional Practice
Your learners get extra practice using coordinates in calculating mid points, finding end points, deciding if points are collinear, calculations using slope concepts, writing linear equations, using triangles and quadrilaterals, and...
Mathematics Vision Project
Module 6: Congruence, Construction, and Proof
Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This...
Education Development Center
Similar Triangles
Model geometric concepts through a hands-on approach. Learners apply similar triangle relationships to solve for an unknown side length. Before they find the solution, they describe the transformation to help identify corresponding sides.
EngageNY
Rearranging Formulas
Model for your learners that if they can solve an equation, they can rearrange a formula with a well-planned activity that has plenty of built-in practice. As the activity progresses the content gets progressively more...
EngageNY
More About Similar Triangles
Determine whether two triangles are similar. The lesson presents opportunities for pupils to find the criterion needed to show that two triangles are similar. Scholars use the definition of similarity to find any missing side...
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...
EngageNY
Complex Numbers and Transformations
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...
Illustrative Mathematics
Equal Area Triangles on the Same Base II
A deceptively simple question setup leads to a number of attack methods and a surprisingly sophisticated solution set in this open-ended problem. Young geometers of different strengths can go about defining the solutions graphically,...
Curated OER
Introduction to Conics
Just exactly where does the name conic come from? This brief hands-on exploration explains it all. Have your class cut cones to create their own conics, then assess their understanding with a few identification problems. Consider making...