EngageNY
Informal Proof of AA Criterion for Similarity
What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply...
5280 Math
Factory Functions
Solve a real-life problem using function-building skills. Presented with an open-ended question, scholars complete a checklist to create and justify a solution in an interesting algebra project. The checklist asks for justifications of...
Concord Consortium
Flying High
Some planes are just more efficient than others. Young mathematicians use data on the number of seats, airborne speed, flight length, fuel consumption, and operating cost for airplanes to analyze their efficiency. They select and use...
Radford University
Natural Disaster Recovery and Quadrilaterals: Trapezoids and Land Assessments
After a tornado, an insurance company is in need of finding the area of a plot of land. Pupils use their knowledge of trapezoids and area formulas to calculate the area of the plot of land. The scholars work in groups to justify the...
Heritage Foundation
Lawmaking and the Rule of the Law
How many constitutional clauses does it take to create a bill? High schoolers find out with several activities and selected clauses about the rule of law and the US Constitution. Various coinciding activities help to strengthen learning.
Curated OER
Fraction Food Frenzy
Young scholars study addition of fractions with like denominators using illustrations and problem solving.
Curated OER
Modeling Conditional Probabilities 1: Lucky Dip
Check out this detailed lesson plan on conditional probability! Learners work individually and also collaboratively to analyze the fairness of a game and justify their reasoning. it includes detailed notes and many helpful suggestions...
NPR
Civil Rights of Japanese-American Internees
Prompted by a viewing of Emiko and Chizu Omori’s Rabbit in the Moon, a documentary about the internment of Japanese-Americans during World War II, high schoolers examine a series of documents, including the Bill of Rights and the UN’s...
Curated OER
Rational and Irrational Numbers 1
You'll need scissors, glue sticks, and mini whiteboards for this activity on rational and irrational numbers. Learners work in groups to classify a variety of expressions as rational or irrational. They are also given a mock discussion...
Curated OER
Investigation-Reasoning and Proof
Third graders determine the outcome of each of the following situations and justify their findings: even number + even number = ?, even number + odd number = ?, odd number + odd number = ?, and odd number + even number = ?.
California Education Partners
Science Fair Project
Plant the data firmly on the graph. Given information about the growth rate of plants, pupils determine the heights at specific times and graph the data. Using the information, scholars determine whether a statement is true and support...
Inside Mathematics
Two Solutions
Many problems in life have more than one possible solution, and the same is true for advanced mathematics. Scholars solve seven problems that all have at least two solutions. Then three higher-level thinking questions challenge them to...
Inside Mathematics
Magic Squares
Prompt scholars to complete a magic square using only variables. Then they can attempt to solve a numerical magic square using algebra.
Illustrative Mathematics
Tilt of Earth's Axis and the Four Seasons
Geometry meets earth science as high schoolers investigate the cause and features of the four seasons. The effects of Earth's axis tilt features prominently, along with both the rotation of the earth about the axis and its orbit about...
EngageNY
Solving a Linear Equation
Solving an equation is the art of creating simpler equivalent equations using properties of equality. Here, classes see that solving an equation is not always as easy as guessing. The instructional activity presents linear equations that...
Curated OER
Life is Full of Problems
Pupils use the problem solving strategy of guess and check to investigate math word problems. They determine which problem solving strategy or strategies would work best in problem situations.
Curated OER
The 3 R's of Common Denominators (Language)
Students solve various word problems that deal with common denominators, and write the mathematical explanations they used to obtain the solutions.
Curated OER
Toothpick Triangles
Explore patterns, variables, and mathematical relationships when you examine patterns with toothpicks and determine the next sequence of figures. Your class writes and justifies a formula based on the sequence. An answer key is included.
Workforce Solutions
On the Job
Four lessons spotlight a variety of professions while boosting listening and observational skills and making inferences. Lesson one challenges pupils to group cards based on a commonality then justify the relationship they see. Lesson...
Curated OER
Exercise Set 2.7: Functions and Graphs
In this functions worksheet, students solve 40 short answer problems. Students determine if a graph represents a function. Students find the domain of absolute value and square root functions.
Curated OER
Rate and Concentration
Experimental data for a chemical reaction is available in a table. Chemistry cohorts use critical thinking skills to analyze the data and answer questions about reaction rates and reaction order. This activity is neatly formatted,...
Illustrative Mathematics
Rational or Irrational?
Is 4 plus the square root of 2 rational or irrational? After your class has gained a basic grasp of rational and irrational numbers, use this worksheet to push them a little further in their understanding. Learners must identify sums and...
EngageNY
Unknown Angle Proofs—Writing Proofs
What do Sherlock Holmes and geometry have in common? Why, it is a matter of deductive reasoning as the class learns how to justify each step of a problem. Pupils then present a known fact to ensure that their decision is correct.
Curated OER
Test Your Speaking & Listening Skills: How To Give a Small Group Or Individual Presentation
How do you structure oral presentations? Guide your orators with this plan. Groups of English language learners will practice presenting their opinion in response to the question "Do you think the death penalty is justified for some...