EngageNY
Triangle Congruency Proofs (part 2)
Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...
EngageNY
Similarity
Learn similarity through a transformations lens! Individuals examine the effects of transformations and analyze the properties of similarity, and conclude that any image that can be created through transformations is similar. The...
EngageNY
Congruence Criteria for Triangles—ASA and SSS
How do you know if a pair of triangles are congruent? Use the lesson to help class members become comfortable identifying the congruence criteria. They begin with an exploration of ASA and SSS criteria through transformations and...
EngageNY
Between-Figure and Within-Figure Ratios
Tie the unit together and see concepts click in your young mathematicians' minds. Scholars apply the properties of similar triangles to find heights of objects. They concentrate on the proportions built with known measures and solve to...
Curated OER
Polygons All Around Us!
Students explore the concept of polygon properties. In this polygon properties lesson, students draw polygons with different numbers of sides such as pentagons, octagons, hexagons, etc. Students identify different geometric shapes in the...
EngageNY
Triangle Congruency Proofs (part 1)
Can they put it all together? Ninth graders apply what they know about proofs and triangle congruence to complete these proofs. These proofs go beyond the basic triangle congruence proofs and use various properties, theorems, and...
Curated OER
Congruent Triangles
High schoolers explore the concept of congruent triangles. In this congruent triangles lesson, students use Cabri Jr. to construct two congruent triangles using circles. High schoolers determine if the two triangles are...
Houghton Mifflin Harcourt
Similar Polygons and Circles
In these similar polygons and circles worksheets, students complete 15 questions including 9 word problems regarding similar polygons. Students then complete 15 questions including 1 word problem involving circumference, area, and arc...
Alabama Learning Exchange
Triangle Congruence with Rigid Motion
Combine transformations and triangle congruence in a single lesson. Scholars learn to view congruent triangles as a rigid transformation. Using triangle congruence criteria, learners identify congruent triangles and the rigid...
Curated OER
Chapter 5 Final Review Extra Problems. Triangles
In this triangles worksheet, students identify the median, altitude, segment, angle bisector, perpendicular bisector and triangle midsegment of triangles. They find the perimeter of triangles. This three-page worksheet...
Inside Mathematics
Patterns in Prague
Designers in Prague are not diagonally challenged. The mini-assessment provides a complex pattern made from blocks. Individuals use the pattern to find the area and perimeter of the design. To find the perimeter, they use the Pythagorean...
Noyce Foundation
Parallelogram
Parallelograms are pairs of triangles all the way around. Pupils measure to determine the area and perimeter of a parallelogram. They then find the area of the tirangles formed by drawing a diagonal of the parallelogram and compare their...
Illustrative Mathematics
Hexagonal Pattern of Beehives
Young geometers and biologists investigate the math of nature in an activity that is just the bee's knees. Participants will study the tessellations of hexagons in a beehive, along with the natural rationale behind the specific shape....
Noyce Foundation
Granny’s Balloon Trip
Take flight with a fun activity focused on graphing data on a coordinate plane. As learners study the data for Granny's hot-air balloon trip, including the time of day and the distance of the balloon from the ground, they practice...
Curated OER
Math: Arcs and Chords
Learners draw diagrams demonstrating how it is possible to two central angles to be congruent and their minor arcs are not congruent. In groups, they illustrate theorems with their constructed circles, create diameters of circles that...
Curated OER
Tennis Triangle
Students calculate the height of a tree or flagpole. They measure the shadow of the tree or flagpole and the length of a shadow of a meterstick. Using similar triangles, calculate the heigh. Devise two additional ways in which to measure...
Curated OER
Dilation
Tenth graders identidy and define various geometry terms, Students create exact replicas of a shape that is either smaller or larger than the original shape. Students prove that their entire shapes are larger or smaller in the same...
Curated OER
Proofs
In this geometric proof activity, students compose 20 triangle congruency proofs. Kids will decide if there is enough information in problems 1-6 to prove if any triangles are congruent. In problems 17 to 20, students use given...
Curated OER
The Truth About Triangles And Proofs
Students engage in a lesson that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the importance of...
Curated OER
Reflections in the Plane
Have your class explore the concept of reflections as they use Cabri Jr. to construct a triangle and reflect it over a line. Learners reflect shapes across the coordinate plane and across the lines y = x and y = -x.
Curated OER
Sled Kite Proportions
Learners build sled kites. in this kite building lesson, students must read directions for kite building and enlarge the proportions of the given kite pattern. Learners focus on the angles and line of symmetry in their kite.
Curated OER
Congruent Trianges - Is This Enough Information?
Seventh graders determine whether two triangles are congruent and provide an explanation to why they are not. They apply concepts of measurement of angles and collect evidence of congruent angles in the world.
Curated OER
Translating Words to Algebraic Expressions
Seventh graders translate word sentences to algebraic expressions. In groups of three, 7th graders determine the number of times their heart beats in fifteen seconds. Using this data, they calculate the heartbeats per minute, in five...
Curated OER
Fractals
Students explore the concept of fractals. In this fractal lesson, students use applets to explore Koch's Snowflake, Sierpinski's Triangle, and other fractals. Students develop these concepts through exploration and teacher guided...