Assessment
Mathed Up!

Proof

For Students 9th - 12th Standards
Scholars learn how to write number theory proofs by viewing a video reviewing techniques for proofs on divisibility, parity, and consecutive integers. They then write proofs for a handful of conjectures on a worksheet.
Worksheet
Curated OER

Easy Worksheet: Counterexamples

For Students 9th - 12th
In this counterexamples worksheet, high schoolers solve 10 short answer problems. Students prove the given statements false by providing a counterexample thus disproving the statement.
Lesson Plan
EngageNY

The Converse of the Pythagorean Theorem

For Teachers 8th Standards
Is it a right triangle or not? Introduce scholars to the converse of the Pythagorean Theorem with a lesson that also provides a proof by contradiction of the converse. Pupils use the converse to determine whether triangles with given...
Assessment
Inside Mathematics

Quadrilaterals

For Teachers 9th - 12th Standards
What figure is formed by connecting the midpoints of the sides of a quadrilateral? The geometry assessment task has class members work through the process of determining the figure inscribed in a quadrilateral. Pupils use geometric...
Worksheet
Curated OER

Write the Counterexample

For Students 8th - 11th
In this counterexample worksheet, students provide counterexamples for the four given statements.  The solutions are not provided.
Worksheet
Curated OER

Inductive Reasoning and Conjecturing

For Students 10th
In this inductive reasoning and conjecturing worksheet, 10th graders solve 4 problems that include applying inductive reasoning and conjecturing to each problem. First, they determine if each conjecture is true or false based on the...
Worksheet
Curated OER

Divisibility Rules

For Students 8th - 9th
In this divisibility rules worksheet, students solve 18 different problems that include applying the divisibility rules to each. First, they identify the hypothesis and conclusion in logical deduction. Then, students determine the...
Worksheet
Curated OER

Geometry Concepts and Applications

For Students 10th
In this concepts and applications review activity, 10th graders solve and complete 40 various types of multiple choice problems. First, they write the equation of a vertical line passing through a point. Then, students find the...
Worksheet
Curated OER

If-Then Statements and Postulates

For Students 10th
In this if-then statements and postulates instructional activity, 10th graders solve 16 various types of geometry problems that include identifying the hypothesis and conclusions of each conditional statement. Then, they write each...
Assessment
Inside Mathematics

Rhombuses

For Teachers 9th - 12th Standards
Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...
Worksheet
Curated OER

Challenge: Skills and Applications Lesson 1.3

For Students 10th - 12th
In this skills worksheet, students explain the Segment Addition Postulate, provide examples and counter examples and determine congruent line segments.  This one-page worksheet contains 11 multi-step problems.
Lesson Plan
Virginia Department of Education

Similar Triangles

For Teachers 9th - 11th Standards
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...