Senior Sessions

Twice a week (weekdays)
2:00 pm to 2:45 pm ET (New York)



Seniors citizens, exercise your brain in 45-minute math sessions!  Join MoMath’s experienced presenters for intriguing classes on a variety of stimulating topics, including topology, puzzles, and cryptography.  Enjoy the discovery and challenges in these engaging, interactive activities with a collegial cohort of mature minds.  For senior citizens / mature adults.  Online registration closes 15 minutes before each session begins.

Please note that sessions of the same name are repeated sessions.

Senior Sessions: “Möbius Mischief”
Monday, January 24, 2:00 pm ET (New York)
Participants construct fascinating topological objects such as Möbius bands, discovering their fundamental patterns and structures.  Hands-on activities lead participants to discover the surprising properties hidden in these surfaces!  Materials needed: 4 strips of paper (2 inches by 11 inches), scissors, tape, and two different colored pens (or pencils or markers).

Register for “Möbius Mischief” on January 24

Senior Sessions: “Math in the Corner Pocket”
Thursday, January 27, 2:00 pm ET (New York)
Explore angles and the law of reflection while tracing the path of a billiard ball as it bounces off the walls of a pool table.  Use patterns to discover a simple method to predict in which pocket the ball will land and learn how to prove your prediction is correct.  Game on!  Materials needed: pencil, ruler, and graph paper (printout available).

Register for “Math in the Corner Pocket” on January 27

Senior Sessions: “Vote Counts: Packing and Cracking”
Tuesday, February 1, 2:00 pm ET (New York)
Get a glimpse into the mathematics of elections by becoming a “legislator” for a day.  Explore how election districts are drawn, including “packing,” “cracking,” and the meaning of wasted votes, in order to analyze the fairness of representation in an election.  Materials needed: pencil, pen, colored pens (or markers), and printout to be provided.

Register for “Vote Counts: Packing and Cracking” on February 1

Senior Sessions: “Roping Around the World”
Friday, February 4, 2:00 pm ET (New York)
Come test your intuition with a mathematical problem about a rope tied around the Earth.  Explore the counterintuitive solution with an engaging, hands-on activity.  How can we use C=2*pi*r to understand this intriguing problem?  Learn how simple models can help us better understand concepts that defy logic.  Materials needed: pencil, ruler with inch measurements, tape, 3 paper clips, scissors, and sheet of 8-½ x 11 paper cut lengthwise into ½-inch strips.

Register for “Roping Around the World” on February 4

Senior Sessions: “Breaking Codes”
Monday, February 7, 2:00 pm ET (New York)
How do computers keep your passwords secret?  How do websites safeguard your credit card numbers?  Explore multiplicative ciphers, broken codes, and prime numbers, while encoding and decoding your own secret messages.  Learn how cryptography helps protect your private information.  Materials needed: pencil, paper, and calculator (optional).

Register for “Breaking Codes” on February 7

Senior Sessions: “Vote Counts: Tower of Power”
Thursday, February 10, 2:00 pm ET (New York)
Explore the different ways power can be distributed in weighted voting systems.  These systems are those in which different groups have different numbers of votes, such as county delegations, government committees, and even the United States Electoral College.  Should the largest populations have the most power?  Should smaller groups have a voice?  Answering these questions is far more complex than simple majority rule, but modern mathematical analysis provides a useful lens through which to analyze unbalanced voting power.  Materials needed: pencil and paper.

Register for “Vote Counts: Tower of Power” on February 10

Senior Sessions: “Math in Art: Tessellations”
Tuesday, February 15, 2:00 pm ET (New York)
Discover the wonderful world of tessellations!  Explore how geometric shapes can completely cover a plane with no gaps or overlaps and discover where tessellations appear: in nature, in ancient Roman mosaics, in Islamic art and architecture, in quilting patterns, and in the works of modern artists such as M.C. Escher.  Join us to build your own tessellations with regular polygons in this first offering in the new “Math in Art” series.  Materials needed: pencil, paper, scissors, printout to be provided, and pattern blocks set (optional).

Register for “Math in Art: Tessellations” on February 15

Senior Sessions: “Finding Fibonacci”
Friday, February 18, 2:00 pm ET (New York)
1, 1, 2, 3, 5, 8, 13, . . . The Fibonacci sequence is one of the most famous number patterns in all mathematics.  Join us to solve intriguing puzzles, explore hidden patterns, and discover the fascinating secrets that are concealed within this very special arrangement of numbers.  Materials needed: pencil, paper, and colored pens or markers (2 different colors).

Register for “Finding Fibonacci” on February 18

Senior Sessions: “Cryptarithmetic”
Monday, February 21, 2:00 pm ET (New York)
Arithmetic is fun, but arithmetic with letters is even better!  Using process of elimination and clever logic, we will explore fundamental properties of base-10 arithmetic in a unique and challenging way.  Join us for CRYPT4R1THM3T1C! Materials needed: pencil and paper.

Register for “Cryptarithmetic” on February 21

Senior Sessions: “Tangram Teasers”
Thursday, February 24, 2:00 pm ET (New York)
Exercise your mind and stretch your spatial reasoning while searching for solutions to fun tangram puzzles.  Learn to create specific figures by combining seven polygons.  If you get stuck, try another way!  Discover multiple strategies to solve these classic dissection puzzles.  Materials needed: scissors, printout to be provided, and tangram puzzle set (optional).

Register for “Tangram Teasers” on February 24

Senior Sessions: “Topological Tic-Tac-Toe”
Tuesday, March 1, 2:00 pm ET (New York)
The familiar game of tic-tac-toe becomes fun and challenging when played on alternative topological surfaces.  The typical 3×3 game board is enhanced by gluing pairs of opposite edges together in various ways, making for more interesting games and mind-bending playing spaces.  Participants learn to appreciate the ins and outs of these new objects as they develop strategies to master the mathematically enhanced games.  Materials needed: pencil and paper.

Register for “Topological Tic-Tac-Toe” on March 1

Senior Sessions: “Exhibit Explorations: Pythagorean Puzzlers”
Friday, March 4, 2:00 pm ET (New York)
The Pythagorean theorem is one of the most important results in all of mathematics.  There are more than 120 geometric proofs currently known!  Explore geometric proofs in this hands-on workshop based on MoMath’s Time Tables puzzler.  Materials needed: pencil, paper, colored pens (or pencils/markers), ruler, scissors, and graph paper (printout available).

Register for “Exhibit Explorations: Pythagorean Puzzlers” on March 4

Senior Sessions: “Fractal Fascinations”
Monday, March 7, 2:00 pm ET (New York)
Fractals are beautiful and mysterious objects with properties that defy the normal rules of geometry, often consisting of iterated, miniature versions of themselves.  Learn about the most famous fractals and what makes them so unusual.  Materials needed: pencil and paper.

Register for “Fractal Fascinations” on March 7

Senior Sessions: “Exhibit Explorations: Math Square
Thursday, March 10, 2:00 pm ET (New York)
The interactive Math Square floor is the centerpiece of the Museum’s lower level, and among its varying programs is a Voronoi diagram, which creates colorful polygons under your feet.  Learn exciting details about this Museum exhibit and also how to make your very own Voronoi diagram.  Materials needed: pencil, paper, colored pens (or pencils/markers), and ruler (triangle ruler optional).

Register for “Exhibit Explorations: Math Square” on March 10

Senior Sessions: “Math of the Pandemic”
Tuesday, March 15, 2:00 pm ET (New York)
Pandemics affect individuals and groups differently.  Explore how individual choices may determine, for example, the trajectory of the COVID-19 pandemic in the population.  Get a glimpse of game theory, a branch of mathematics that provides us with the tools to understand and analyze these important interactions.  Materials needed: pencil and paper.

Register for “Math of the Pandemic” on March 15

Senior Sessions: “Hailstone Numbers”
Friday, March 18, 2:00 pm ET (New York)
Hail is formed when ice repeatedly travels up and down within a cloud, growing and shrinking until its mass is steady enough to fall to the ground as hail.  Hailstone numbers are repeated patterns of numbers with the same property.  They increase and decrease sporadically according to a set rule until they finally plummet in size and eventually become the number 1.  These number sequences are easy to create but often impossible to fully understand.  Come learn what these numbers are, why they are so mystifying, and how they might just represent the next big breakthrough in mathematics.  Materials needed: pencil and paper.

Register for “Hailstone Numbers” on March 18

Senior Sessions: “Dynamic Dice”
Monday, March 21, 2:00 pm ET (New York)
What is the probability of rolling a given sum with a pair of standard dice?  Explore how to determine that probability and then challenge yourself to find a different way to number the dice to get the very same probabilities.  Come roll the dice!  Materials needed: pencil and paper.

Register for “Dynamic Dice” on March 21

Senior Sessions: “Rep-tiles”
Thursday, March 24, 2:00 pm ET (New York)
Come discover mathematical rep-tiles, geometric shapes that can tile into repetitions of themselves.  Learn about scaling, special tessellations, and mathematical proofs, while solving fun rep-tiles puzzles.  Materials needed: pencil, paper, printouts to be provided, and scissors (to cut out shapes prior to session).

Register for “Rep-tiles” on March 24

Senior Sessions: “Alternative Perspectives
Tuesday, March 29, 2:00 pm ET (New York)
Recently featured in MoMath’s Composite gallery, artist Anton Bakker’s work will take you on a journey into a world of mathematical beauty with an added twist: a change in perspective seems to change the very reality of the object before us.  Lines, curves, knots, spirals, Möbius strips, optical illusions, and fractals — all are explored in this highly engaging virtual tour.  Discover these stunning sculptures and try your own hands-on activities!  Materials needed: pencil, paper, scissors, tape, and colored pens or markers (2 to 4 colors).

Register for “Alternative Perspectives” on March 29


Please note that program fees are non-refundable.  This program is for adults; MoMath reserves the right to remove children from a session without refund.

Share the gift of math!  Gift registrations for Senior Sessions available at