• Classroom Resource Monthly Featured Resources Archive


    NCTM offers a featured resource in your grade band each month to help you make the most of your NCTM membership. 


    May 2021

    Elementary (K-5)

    Shape Tool (Pre K-2)    
    Students have the chance to make a variety of shapes and explore how shapes can be rotated and flipped with this interactive activity!

    Eggsactly with 18 Eggs (3-5)   
    Students demonstrate various fractional amounts of the 18 eggs in the carton by either adding or removing eggs. Students justify their choices and give evidence about their mathematical thinking.

    Middle School (6-8)

    Fishing for the Best Prism 
    Students use polydrons to build nets to create rectangular prisms. They have to make sense of their understanding of nets to calculate surface area and volume of cubes and rectangular prisms. Excellent opportunity for students to "fish" out the mathematical details of a tank.

    High School (9-12)

    Capture-Recapture
    Spring is here and birds are abundant. In this lesson about robin birds, students have opportunities to estimate and define terms in ways that will provide teachers an understanding of their proportional reasoning. Tell us how you elicited and used evidence of student thinking with Capture-Recapture!

    April 2021

    Elementary (K-5)

    Who's in the Family (Pre K-2)    
    Students make connections between addition and subtraction to understand Who's in the Family?

    Petals Around the Rose (3-5)   
    In observing the rolls of five die, students are encouraged to deduce the "number of petals on the rose". By keeping an organized list of rolls and number of petals, students will use discourse to discover the pattern to reveal the answer. This task is more about the process than the final answer.

    Middle School (6-8)

    Mathematics as Communication
    In this lesson that addresses functions in a practical way, students will see real life videos and determine how to produce this image on a graph. They will have to decide how these difference life scenarios should be graphically displayed over time.

    High School (9-12)

    Static Nim
    Static Nim is a one-pile game between two players. In this lesson, students will learn that solving a game means satisfying properties and lots more!

    March 2021

    Elementary (K-5)

    Hopping Backwards to Solve a Problem (Pre K-2)    
    Students use number lines to help them visualize mathematics and ask questions about the relationships between numbers. 

    Describing Designs (3-5)   
    Students use 3-inch squares to create quilt pieces. By designing plane figures inside the squares, they will practice fractional vocabulary as they verbally describe their square to their partner so they can recreate it.

    Middle School (6-8)

    Pan Balance - Expressions
    Do you have middle level students who struggle with abstract concepts such as balancing equations? If you answered yes, the pan balanced interactive scale is a great tool to help students in a virtual environment practice algebraic expressions, equations and equality. 

    High School (9-12)

    Stacking Squares
    What does it mean to complete the square? Using this Illuminations Interactive, students will be able to complete a proof for completing the square accompanied by a tool for visual representation!

    February 2021

    Elementary (K-5)

    Hopping Backwards to Solve a Problem (Pre K-2)    
    Students use number lines to help them visualize mathematics and ask questions about the relationships between numbers. 

    Building a Business (3-5)   
    In building their own businesses, students will engage in selecting products to build, then transition to generating their own questions to answer as they plan revenue streams. Concepts such as pricing, business location, marketing make this a fun and challenging activity.

    Middle School (6-8)

    Dirt Dash
    An investigative lesson where students use concepts such as slope and the Pythagorean Theorem to decide which terrain to travel through and why. Throughout this lesson students ask purposeful questioning through mathematically inquiry to solve. A hands on lesson with videos and technology. 

    High School (9-12)

    Proof Without Words: Completing the Square
    Stacking Squares provides a way for students to develop an understanding of radicals. As students explore in this lesson, teachers are encouraged to pose purposeful questions that will advance student thinking in groups and as individuals.

    January 2021

    Elementary (K-5)

    Ten Frames, and Baseball Games (Pre K-2)    
    Students rotate roles and responsibilities to record the wins, losses, and equations associated with Baseball games. 

    Seeing Geometry in Art (3-5)    
    Students will identify various geometric shapes in art work from different cultures. They will not the frequency of shapes used by different artists.

    Middle School (6-8)

    State Names
    Students use multiple representations to display how many times the letters of the alphabet is used in a state name. Concepts explored: stem and leaf, box* whisker plots, histograms. 

    High School (9-12)

    Building Connections
    This month CRC is promoting the use of representations and Building Connections provides many opportunities for students to do just that! In this lesson students translate between pictorial, written, and verbal representations of polynomials!

    December 2020

    Elementary (K-5)

    Shirt Full of Buttons (Pre K-2)    
    Students count the number of buttons they are wearing and the work together to create a graph. In the virtual environment, this graph could be created using a slides presentation or online whiteboard. Outside graphics or objects could be incorporated as the the button source.

    Found Pounds (3-5)    
    Students will use food to demonstrate the difference between pounds and ounces.

    Middle School (6-8)

    Shops at the Mall
    Students are tasked to determine and research which stores in the mall are less or more prevalent during this day and age. Scale modeling and percent of space used are vital concepts that are used throughout the activity. 

    High School (9-12)

    Pinwheel
    December 16th is Pythagorean Theorem Day! First, find out why! Then, apply the theorem to calculate the lengths of diagonals in Pinwheel.

    November 2020

    Elementary (K-5)

    Creating, Describing, and Analyzing Patterns (Pre K-2)    
    Students can explore and set the level of challenge they would like for making and continuing patterns in this Illuminations interactive.

    Analyzing Designs (3-5)    
    Students will explore rotational symmetry by creating their own unique quilts. Students will predict the effects of their design choices on the design with regard to turns, slides and flips.

    Middle School (6-8)

    How Did I Move?
    Collaboratively, students investigate movement on a football field to apply the concepts of functions and systems of equations.

    High School (9-12)

    Is the Fair Fair?
    Is the Fair Fair? Students figure out the probability of winning a game in this lesson but its a fantastic resource for teachers too! Examples of student responses in the teacher packet demonstrate the various ways that the learning goal can be mastered.

    October 2020

    Elementary (K-5)

    Making Tens: Finding Addends that Sum to Ten (Pre K-2)
    Students have the chance to explore the combinations of ten in this hands-on activity.

    Odd Man Out: Identifying Sums of Numbers as Odd or Even (3-5)
    Students will explore the meanings of odd and even as they analyze sums of addends. The use of partner work is well-suited for illustrating odd and even and provides natural discourse about mathematics.

    Middle School (6-8)

    Why is California so Important?
    Students investigate the differences to decide how a president gets elected using population and electoral college data. Central tendency will be used throughout the lesson.

    High School (9-12)

    Number Representations
    October 10th is Powers of Ten 10 Day! In this lesson, Number Representations, students are asked to interpret a numeral given in a base other than 10 as a sum of multiples of powers of that base, b. 

    September 2020

    Elementary (K-5)

    See It, Move it, Grasp It: Math with Virtual Manipulatives (Pre K-2)
    Help students learn to visualize and talk about similarities and differences. This lesson integrates poetry with geometry for a great community building activity.

    Create an Address Number (3-5)
    Students will find a three-digit address for a building according to certain rules. Through guidance and working together, students will discover that making a list is more efficient than random guessing.

    Middle School (6-8)

    Exploring Transformations
    Students will explore properties of transformations to discover patterns through generalizations, and developing rules. 

    High School (9-12)

    Creativity and Storytelling in Mathematics Lessons  
    September 25th is Math Story Telling Day! In this webinar, educators explore how storytelling and real-life applications can make the content more accessible and engaging, and how creativity and problem-solving can show students the great power and surprising beauty of mathematics.

    August 2020

    Elementary (K-5)

    Shapes and Poetry (Pre K-2)
    Help students learn to visualize and talk about similarities and differences. This lesson integrates poetry with geometry for a great community building activity.

    First Names First (3-5)
    Students will get to know each other through collecting and classifying the number of vowels in first names. They will create graphs for this purpose. Also gives an opportunity for discussion of cultural names.

    Middle School (6-8)

    Elections: Picking a Winner
    Students will investigate the role of math in the presidential election process with Electoral College using multiple probability counting methods to determine the winner.

    High School (9-12)

    Mix it Up    
    In Mix it Up, students will estimate percent concentration in mixes and then they will develop a strategy for final calculations. Mathematics is better when done together and there are many opportunities for collaboration in this hands on lesson!

    July 2020

    Elementary (K-5)

    Concentration (Pre K-2)
    Individually or against a friend, students match whole numbers, shapes, fractions, or multiplication facts to equivalent representations.

    Eating Grapes (3-5)
    In this problem, students will discover a rule for a pattern. Student may use examples until they are able to generalize to any case.

    Middle School (6-8)

    Finding the Balance
    Using tools that can be found around the home, students construct a two-pan balance and discover relationships between the length of the arm of a fulcrum and the mass of objects.

    High School (9-12)

    Growth Rate              
    Use height vs. age charts to approximate rates of change at single points on a non-linear graph.

    June 2020

    Elementary (K-5)

    See it, Move it, Grasp it: Math with Virtual Manipulatives (Pre K-2)
    Children create and describe designs using various pattern blocks. This is an open ended task that is fun for all ages!

    Odds and Evens (3-5)
    Students investigate fairness given a friendly game with spinners. Teachers can connect the idea of fairness to justice in the real world.

    Middle School (6-8)

    Pinwheel
    By constructing a model of an octagon that transforms into a pinwheel, students realize that many interesting geometric shapes occur that can be explored. Print or replicate the materials for this activty, or try using virtual manipulatives! 

    High School (9-12)

    Changing Places              
    Moving one chip at a time, and alternating colors, challenge your students to exchange the red chips for the blue chips in only 22 moves.

    May 2020

    Elementary (K-5)

    Pattern Block Designs

    If you wanted to build this design out of totally different blocks, what pattern blocks could you use?

    Pattern Block Fractions

    Can you find another way to use fraction pattern blocks and combine them to make one whole?

    Middle School (6-8) 

    Paving Stones

    In Paving Stones students are asked to find students are asked to find how many stones Kathy needed to buy to pave an area in her yard.

    High School (9-12) 

    The Rolling Triangle

    Equilateral triangle ABC is sitting on the top of square DEFG so that AC is coincident with DE. The triangle and square both have edges one unit in length.

    April 2020

    Elementary (K-5)

    Sum Search

    Children focus on finding sums while practicing the secondary skills of subitizing and explaining their thinking. Grab some dominoes and a hundreds chart to get started! 

    Darlene's Dart Board

    Can your students hit the target? Students will apply reasoning to find combinations of targets that total exactly 100 points. 

    Middle School (6-8) 

    A Day at the Fairs

    The problem this week is an old one, in fact over 500 years old. It goes back to the days in Europe when fairs were common in many cities, and merchants would travel from city to city, selling their various goods and buying other items they desired. A merchant went selling and buying at three city fairs. Did he make a profit or take a loss? 

    High School (9-12) 

    Four Men and Some Money

    This short but sweet Problem of the Week asks students to use algebraic reasoning to divide $100 among four people.

    March 2020

    Elementary (K-5)

    Counting on and Counting Back

    Help your students visualize the idea of "one more" and "one less" with this interactive lesson. All you need is a counting book and some counting cubes to get started!

    March Madness

    Students evaluate clues to arrive at correct outcome of game: scores of two teams.

    Middle School (6-8) 

    The Factor Game

    Students will love The Factor Game! It engages students in a friendly contest in which winning strategies involve distinguishing between numbers with many factors and numbers with few factors. Students are then guided through an analysis of game strategies and introduced to the definitions of prime and composite numbers.

    High School (9-12) 

    The 100 Block Walk for Math

    To celebrate the 100th Mathematical Lens column, Ron Lancaster and Bridget Bentele walked 100 blocks through Manhattan, photographing and documenting the mathematics they encountered along the way.

    February 2020

    Elementary (K-5)

    A Picture is Worth 100 Math Ideas

    Get ready to celebrate 100 with this technology infused mathematics activity. Students take the lead and photograph objects of varying amounts, increasing their understanding of place value and precision of language along the way.

    Building Bouquets

    This task asks students to apply the knowledge of divisors, dividends and remainders to solve a real world task. Students must form questions that will allow them to solve through productive struggle.

    Middle School (6-8) 

    If You Like Popcorn, Which One Would You Buy?

    This is a great math game for probability! Students love playing this game. You can have great discussions with students about whether or not they want to keep playing or bow out.

    High School (9-12) 

    All Around the World

    This 100-themed Problem of the Week leads to a result that may surprise you and your students.

    January 2020

    Elementary (K-5)

    Counting Back and Counting On

    The Concrete, Representational, and abstract intersect in this hands-on lesson while also integrating literature and musical connections.

    Every Breath You Take

    Students estimate the number of breaths they take, then perform an experiment to find the actual amounts.

    Middle School (6-8)

    The Game of SKUNK

    This is a great math game for probability! Students love playing this game. You can have great discussions with students about whether or not they want to keep playing or bow out.

    High School (9-12)

    Axonometry: Applying Complex Numbers to Art

    Axonometry is an Illumination that has students discover relationships between complex numbers and graphing. Students make connections between algebraic and graphical representations of a complex number.