EngageNY
Thales’ Theorem
Isn't paper pushing supposed to be boring? Learners attempt a paper-pushing puzzle to develop ideas about angles inscribed on a diameter of a circle. Learners then formalize Thales' theorem and use geometric properties to develop a proof...
Virginia Department of Education
Similar Triangles
Pupils work in pairs to investigate what it takes to prove that two triangles are similar. They work through various shortcuts to find which are enough to show a similarity relationship between the triangles. Small groups work with the...
EngageNY
Are All Parabolas Congruent?
Augment a unit on parabolas with an instructive math activity. Pupils graph parabolas by examining the relationship between the focus and directrix.
Curated OER
Pythagorean Theorem by Graphic Manipulation
There are many different ways to show a proof of the Pythagorean Theorem. Here is a nice hands-on paper cutting activity that shows a graphic representation. You can even challenge your young Pythagoreans to come up with their own...
West Contra Costa Unified School District
Pythagorean Theorem and Its Converse
Challenge scholars to prove the Pythagorean Theorem geometrically by using a cut-and-paste activity. They then must solve for the missing sides of right triangles.
EngageNY
Algebraic Expressions—The Commutative and Associative Properties
Who says math is boring? Turn dry concepts like properties and vocabulary into an interesting lesson! Examine the commutative and associative properties of addition and multiplication using geometric reinforcement. Through collaboration,...
EngageNY
How Do Dilations Map Segments?
Do you view proofs as an essential geometric skill? The resource builds on an understanding of dilations by proving the Dilation Theorem of Segments. Pupils learn to question and verify rather than make assumptions.
Curated OER
Verifying Segment Relationships
In this verifying segment relationships worksheet, 10th graders solve 3 different proofs by verifying the segment relationship in each. They complete each proof given a specific statements supporting the statement with reasons. Then,...
Curated OER
Verifying Segment Relationships
In this verifying segment relationships activity, 10th graders solve two proofs by following the same format used in algebra. They complete each of two proofs by naming the property that justifies each statement given. Students also...
Curated OER
Proving Triangles Congruent
In this proving triangles congruent instructional activity, 10th graders solve 4 different proofs for congruent triangles. First, they mark all congruent parts on each figure, then complete the prove statement and identify the postulate...
Curated OER
Identifying Similar Triangles
For this identifying similar triangles worksheet, 10th graders solve 5 different proofs related to similar triangles. First, they identify the similar triangles in each figure and explain why they are similar, using the information to...
Curated OER
Parallelograms
In this parallelograms worksheet, 10th graders solve 8 different types of problems related to measuring various parallelograms. First, they use the figure, a parallelogram, illustrated at the top to solve each problem. Then, students...
Curated OER
Verifying Angle Relationships
In this angle relationships learning exercise, 10th graders solve 8 various problems related to verifying angle relationships. First, they complete each statement if the measure of specific angles are equal to 43 and 56. Then, students...
Curated OER
Right Triangles
In this right triangles worksheet, 10th graders solve 5 problems that relate to different right triangles. First, they find the values of x and y so that each triangle is congruent to the other. Then, students write a two-column proof...
Inside Mathematics
Circles in Triangles
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
EngageNY
End-of-Module Assessment Task: Grade 8 Mathematics (Module 7)
It's time to discover what your classes have learned! The final lesson in the 25-part module is an assessment that covers the Pythagorean Theorem. Application of the theorem includes distance between points, the volume of...
Curated OER
History / Introduction of Pythagorean Theorem
Learners explore Pythagoras and the history behind his theorem. They work together to solve a proof that is embedded in the instructional activity.
Curated OER
Applied Maximum Minimum Problems--Mini Golf
Twelfth graders investigate maximum and minimum as it relates to billiard and mini golf. In this calculus lesson plan, 12th graders review how to find the maximum and minimum and write proofs to show how they arrive at their answer. They...
Curated OER
Pythagorean Theorem Proof
Tenth graders investigate the Pythagorean Theorem. Then they type up a formal paragraph proof of a proof of their choice.
Arizona Department of Education
Area and Perimeter of Regular and Irregular Polygons
Extend young mathematicians' understanding of area with a geometry lesson on trapezoids. Building on their prior knowledge of rectangles and triangles, students learn how to calculate the area of trapezoids and other...
EngageNY
Construct an Equilateral Triangle (part 2)
Triangles, triangles, and more triangles! In this second installment of a 36-part series, your young mathematicians explore two increasingly challenging constructions, requiring them to develop a way to construct three triangles that...
Curated OER
The Right Stuff
Studentsare introduced to the Pythagorean Theorem by exploring right triangles and the squares built on each side. They apply the Pythagorean Theorem to real-world problems. Students u se informal and nonformal arguments of proof (i.e.,...
Curated OER
Interactivate - Lines, Rays, Line Segments, and Planes
Students explore lines, rays, line segments, and planes. In this math lesson, students discuss the math concepts and direct their instructor in graphing functions. Students collaborate in graphing additional functions.
Shodor Education Foundation
Surface Area of Rectangular Prism
With this interactive instructional activity, learners compute the surface area of rectangular prisms. They visit an online investigation applet and record data on the provided handout. Pair this instructional activity with the volume...