CK-12 Foundation
Conjectures and Counterexamples: An Extra Slice!
Class members will eat up an enticing interactive that lets users change the location of cuts made into a pizza to adjust the number of created slices. They create a counterexample for a conjecture on the number of slices.
CCSS Math Activities
Smarter Balanced Sample Items: High School Math – Claim 3
Communication is the key. A presentation provides 25 sample items for Claim 3, Communicating Reasoning, for the Smarter Balanced High School Math assessment. Items require pupils to answer the question and provide logical reasoning to...
EngageNY
Fraction Multiplication and the Products of Decimals
Class members come up with a hypothesis on the number of decimal digits in the product of two decimals. Learners work in groups to complete several decimal multiplication problems. The results help groups develop a conjecture on the...
Ahisma Summer Institute
The Power of One - Math in a Different Angle
In this 2-day lesson focused on exponents, middle schoolers will cross the curriculum by engaging in science, history and language arts activities. Exponential growth will be explored using grains of rice on a chess board. Exponential...
EngageNY
Modeling with Polynomials—An Introduction (part 1)
Maximizing resources is essential to productivity. Class members complete an activity to show how math can help in the process. Using a piece of construction paper, learners construct a box with the maximum volume. Ultimately, they...
Mathed Up!
Proof
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.
Curated OER
Triangle Conjectures
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. For this geometry lesson, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by...
Curated OER
Polygon Sum Conjecture
In this geometry instructional activity, 10th graders identify the missing angles using the polygons sum conjecture. They measure exterior and interior angles using their angle theorems. There are 63 problems.
Curated OER
Contructions and Conjectures
Students make constructions and conjectures. In this geometry lesson, students construct right, acute and obtuse angles using a straight edge and a protractor. They investigate parallel lines and the angles formed by the angles.
Concord Consortium
Short Pappus
It's all Greek to me. Scholars work a task that Greeks first formulated for an ancient math challenge. Provided with an angle and a point inside the angle, scholars develop conjectures about what is true about the shortest line segment...
GeoGebra
Conjectures and Proof
Transform proofs using triangle rotations. By rotating a triangle around various points, class members develop proofs. Participants prove relationships of alternative interior angles formed by parallel lines and the sum of the interior...
Curated OER
Inductive Reasoning and Conjecturing
In this inductive reasoning and conjecturing activity, 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 given...
Curated OER
Inductive Reasoning and Conjecturing
In this inductive reasoning and conjecturing learning exercise, 10th graders solve 8 different problems that are related to using inductive reasoning and conjecturing. First, they determine if the conjecture is true or false based on the...
West Contra Costa Unified School District
The Parallelogram Law
Use your pupils' sense of curiosity to explore the Parallelogram Law. Here is an activity that outlines a complete lesson plan from beginning to end, allowing pupils to follow a conjecture through to the proof stage.
Curated OER
Rational Exponents
Investigate rational exponents in this math instructional activity. Scholars make conjectures about the relationship between rational exponents and radicals. They then use their Ti-Nspire to simplify rational exponents.
Curated OER
Analyzing Congruence Proofs
Looking at numerous examples of triangles, each with different properties, geometers develop their understanding of congruency. They use the notation of a counter-example to disprove certain conjectures and prove geometric theorems and...
Curated OER
Which Quadrilateral Is It?
Students prove conjectures about geometric figures on the plane or in space using coordinate geometry. They develop fluency in operations with real numbers, vectors and matrices using mental computation or paper-and-pencil calculations...
Radford University
Rocket Quads
How high will it fly? Pairs build straw rockets and launch them at different angles and determine the height and horizontal distance of the flight path. Teams make conjectures about how the angle affects the measured distances and use...
Curated OER
Circle Conjectures
Students are given diagrams and are asked to make a conjecture. In this geometry lesson, students make conjectures of circles. They complete a lab activity to reinforce making conjectures. The first activity addresses a common core...
Curated OER
Conjectures of Intersecting Circles
Students make conjectures of intersecting circles. In this geometry lesson, students observe circles and their position in space. They investigate and observe two and three dimensional objects.
Curated OER
Playing Math Fever
Pupils complete activities to learn notation and uses for positive and negative numbers. For this number system lesson, learners play a game similar to Jeopardy to learn how to solve problems with positive and negative numbers.
EngageNY
Recursive Challenge Problem—The Double and Add 5 Game
Math is all fun and games! Use a game strategy to introduce the concept of sequences and their recursive formulas. The activity emphasizes notation and vocabulary.
Curated OER
Angle Relationships
Students investigate geometric relationship using conjecture about linear pairs and vertical angles. In this geometry lesson, students apply their theorems and previous geometry knowledge to solve for and find angles of linear pairs....
Mathematics Vision Project
Module 3: Geometric Figures
It's just not enough to know that something is true. Part of a MVP Geometry unit teaches young mathematicians how to write flow proofs and two-column proofs for conjectures involving lines, angles, and triangles.