Curated OER
Inductive and Deductive Reasoning
High schoolers use logical arguments and inductive reasoning to make or disprove conjectures. After observing a teacher led demonstration, students discover that the deductive process narrows facts to a few possible conclusions. In...
Curated OER
Deductive and Inductive Reasoning
Students differentiate between inductive and deductive reasoning. In this geometry instructional activity, students identify congruent figures and examine logos for congruency.
Curated OER
Deductive Reasoning
Tenth graders investigate deductive reasoning. In this geometry lesson, 10th graders compare and contrast inductive ns deductive reasoning. Students use deductive reasoning to investigate algebraic proof and explore deductive geometric...
Virginia Department of Education
Logic and Conditional Statements
If there is a conditional statement, then there is a hypothesis and conclusion. Pupils learn how to identify the parts of conditional statements. Class members continue to work with conditional statements and rewrite them in their many...
Curated OER
Two Column Logic Proofs
Students complete two column proofs. In this geometry lesson,students derive the reasons their answers are correct using logic. They write the proof step by step using two columns.
Curated OER
Logic and Proof Writing
Students define inductive and deductive reasoning and write two column proofs. In this geometry lesson, students analyze arguments and draw conclusion. They define steps necessary to arrive at the correct answer when completing proofs.
Curated OER
Inequalities and Triangles
Students prove and apply theorems of triangle inequality and hinge theorem. For this geometry lesson, students will discuss which triangle is bigger and why. They will use theorems, such as Exterior Angle Inequality or the Pythagorean...
Curated OER
Operation Spaghetti
Find the math in recipes. Young chefs will follow a recipe and investigate the total cost for materials. They measure amounts of food necessary for the recipe and compute the per person cost.
Curated OER
Proving Quadrilateral Properties
Working backwards can sometimes help you see a path to solving a problem. In this chapter, properites of quadrilaterials are proven by looking at flowcharts and working the probem backwards. Worked through examples are given, along with...
Curated OER
Geometry and Islam: Religious Beliefs Made Visual
Students examine the importance of geometric patterns in Muslim countries. Using cutout patterns, they replicate the designs seen in Islam and color them. They put their completed designs on a bulletin board to show to the school.
Illustrative Mathematics
Shortest Line Segment from a Point P to a Line L
One of the hardest skills for many young geometers to grasp is to move beyond just declaring obvious things true, and really returning to fundamental principles for proof. This brief exercise stretches those proving muscles as the class...
Illustrative Mathematics
Similar Triangles
Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...
Alabama Learning Exchange
Polygons-Changing Area Versus Changing Perimeter
Investigate the area and perimeter of polygons in this geometry instructional activity. Young geometers use grid paper to draw a quadrilateral and calculate its area and perimeter. They also read The Greedy Triangle to identify the...
Curated OER
U Boat Hunt
Students recognize patterns and sequences in numbers. In this geometry lesson plan, students create rules to define the sequences and patterns they obsere. They translate coded messages as they dicuss navigational terms.
EngageNY
Applications of Congruence in Terms of Rigid Motions
Corresponding parts, congruent parts, congruent corresponding parts—what does it all mean? The resource challenges pupils to identify corresponding parts for pairs of figures. It uses examples of figures that undergo rigid...
Curated OER
Preparation and Transition to Two-Column Proofs
Students investigate proofs used to solve geometric problems. In this geometry lesson, students read about the history behind early geometry and learn how to write proofs correctly using two columns. The define terminology valuable to...
Curated OER
Four Color Map
Students explore geometry by completing a color puzzle. In this shape identification lesson, students utilize deductive reasoning to complete a Google SketchUp puzzle with trapezoid, triangles and rectangular shapes. Students complete...
Curated OER
Water Treatment Plant Tour
Students define vocabulary related to geometry and calculate the volume. In this geometry lesson, students calculate flow rates, and volume as it relates to a water plant facility. They calculate the volume of three dimensional shapes...
Curated OER
Quadrilateral Explorations-Grade Nine
Ninth graders investigate quadrilaterals. In this geometry lesson, 9th graders examine and classify quadrilaterals using the slope, midpoint and distance formulas. Additionally, students create various quadrilaterals given three point...
EngageNY
Construct an Equilateral Triangle (part 1)
Drawing circles isn't the only thing compasses are good for. In this first installment of a 36-part series, high schoolers learn how to draw equilateral triangles by investigating real-world situations, such as finding the location of a...
West Contra Costa Unified School District
Investigating Special Right Triangles
Scholars first investigate relationships in the side lengths of 30°-60°-90° triangles and 45°-45°-90° triangles. This knowledge then helps them solve problems later in the lesson about special right triangles.
Shodor Education Foundation
Sets and the Venn Diagram (Beginner)
Venn diagrams are helpful in understanding the idea of a set and using attributes to sort items. This basic plan is an introduction with an added bonus of an applet that can be used to demonstrate the activity. If a classroom of...
Curated OER
Visualizing Multiplication
Upper graders represent multiplication of a two-digit number by a two-digit number as the area of a rectangle with dimensions of the two factors. They find patterns for the number of different base ten blocks in a rectangle representing...
Curated OER
"A Slice of the Cone"
Here is a set of lessons that explore conics in a number of different ways. Starting with modeling how a conic is produced by the way a plane cuts the cone, to solving complex word problems, algebra learners progress through a series of...