Math Circle at CSUDH Meetings

The CSUDH Math Teacher Circle will meet the first Tuesday of each month during the 2017-2018 academic year. All meetings are from 5:30 - 8:00 pm and dinner will be served!

Check back here for more information on individual meetings.

2017-2018 Meetings

9/5/17 "Simon Says, Four Gallons"

Given a 5 gallon jug and a 3 gallon jug, is it possible to measure out exactly 4 gallons? That's the problem faced by John McClane and Zeus Carver in Die Hard 3. In this session, we'll not only solve this problem, but we will also look at questions such as: Is there a shorter way to do this other than trial and error? How can we use geometry to solve this problem? How is this kind of problem connected to number theory?

Registration for the 9/5 Meeting is closed. Sign up now for the 10/3 Meeting!

10/3/17 "Estimathon"

How many airline passengers are there in a year? How many miles long is the Mississippi River? In this session, we will play a game called Estimathon, where the questions involve giving a range in which you think the correct answer lies. You and your team will have to select your ranges carefully to maximize your score in the game. We will also look at how to use what we learn from one estimate to make estimates of related values and explore estimation tasks you can use with your students. Come and hone your skills at estimation!

Click here for the flyer. Click here to sign up!

11/7/2017 "Candy Sharing"

In this session we will play a game called Candy Sharing. Can you create a game that results in an infinite loop? Can you predict how long the game will last? When is the game over before it begins? In this session, we will investigate these and other questions and see the mathematics of dynamical systems in action.  Come get a taste of candy sharing--the sweetest math!

Click here for the flyer. Click here to sign up!

12/5/2017 "Is Santa Secretly Deranged?"

Have you ever been part of a Secret Santa gift exchange? Did anyone ever draw their own name and have to re-draw? How often does that happen? What happens as the size of the group of participants grows? In this Math Teacher Circle, we look at the mathematics of these exchanges, called derangements. A derangement is a one-way assignment of each person in a group to another person. As the group grows bigger, what happens may surprise you.

Click here for the flyer. Click here to sign up!

2/6/2018 "Pick Connects the Dots"

When it comes to measuring the area of a simple polygon all you have to do is take out a measuring tape and your area formula, right? But what do you do if your simple polygon is not so simple? Is there some way to find the area without measuring all the edges? In this Math Teacher Circle, we take a look at how the connect the dots grid game helps us calculate the area of any simple polygon. Pick’s Theorem will help us do the rest.

Click here for the flyer. Click here to sign up!

3/6/2018 "The Game of Hex"

In this session, we will investigate the game of Hex - a two player “grid” game that seems to always have a winner. Does Hex really always have a winner? Can you discover a winning strategy? Or can your opponent always keep you from winning, as in Tic-Tac-Toe? Come and see what you can find out.

Click here for the flyer. Click here to sign up!

4/3/2018 "Length Spectrum of Numbers"

This session begins with the question, ‘Which natural numbers can be written as sums of (more than one) consecutive natural number’?

Note that a number may be written as such a sum in more than one way, e.g. 9 = 4+5 = 2+3+4. We call the collection of the lengths of these sums the length spectrum of the number, so the lspec(9) = {1,2,3}. In this session we will explore some natural questions that one may ask about these spectra. Along the way, we will have some fun in playing a guessing game. Be prepared for some surprises!

Click here for the flyer. Click here to sign up!

5/1/2018 "Knot Mosaics"

Knot theory is an area of mathematics concerned with, well, knots, loops of string crossed over and around each other in different ways. How can you tell two knots apart, or if two knots are really the same? This is the core of knot theory. In 2008, a new perspective on this theory, knot mosaics, took hold. These mosaics enable a knot to be represented using tiles. In this session, we explore basics of knots and questions such as, What tiles are required to make knot mosaics? How can knots created using mosaics be classified? Come and get tangled up in learning some new mathematics!

Click here for the flyer. Click here to sign up!

Archive of 2016-2017 Meetings

See the links below for more information about each session.

9/6/16 “Pancake Sorting and Recursion”

Have you ever wondered how and where mathematics and computer programming overlap? In this session, we will see that one example of the overlap comes in a very surprising place: pancakes. We will be exploring ideas related to sorting and recursion, and use them to flip our flapjacks into a nicely ordered stack.

 9/6 Session Materials

10/4/16 "Rational Tangle Dance"

In 1967, mathematician John H. Conway presented seminal results on the classification of knots through a study of “rational tangles.” In order to explain some of the key ideas behind the theory, he developed an activity, the “rational tangle dance,” that four people holding the ends of two lengths of rope, and a fifth person looking on, can perform. The magic of this activity has captivated many over the decades, and the rational tangle dance is now considered a favorite in many math circle groups.
Description by James Tanton

10/4 Session Materials

11/1/16 "The Mad Veterinarian: The Mathematics of Mad Science”

In this session, we will explore a situation from science fiction, in which a scientist can transform one animal into others. What mad configurations are possible with an initial set of animals? When can we undo the transformations and get the original animals back? More importantly, what kind of mathematical structures are involved? We will examine these questions and the underlying mathematics involved. White lab coat not required!

11/1 Session Materials

12/6/16 "Pirates, Prisoners and Chicken: An Introduction to Game Theory"

How should a pirate share the loot with fellow cutthroats? Should two captured prisoners each confess to a lesser crime? Did President Kennedy play Chicken with Russia? In this session, we will explore answers to these questions. We will see how these three life-or-death situations are part of a larger mathematical landscape known as game theory, and discuss how game theory can be used in an array of situations to decide on a course of action.

12/6 Session Materials

2/7/17 "SET: The Mathematics Behind the Game"

Set is a fascinating card game developed by Marsha Falco in 1974. The rules specify how certain groups of three cards can be formed to make a "SET". While the rules are fairly straightforward, beneath the surface lurks some deep mathematics. The game leads to questions such as: "How many cards do you need to guarantee a SET?", "How many SETs are possible?", "How is this game like doing geometry?" In this session, we will learn and play SET, and explore some answers to these questions.

2/7 Session Materials

3/7/17 "KenKen"

Invented by Japanese math teacher Tetsuya Miyamoto, KenKen is a popular puzzle that enables the player to exercise arithmetic skills as well as logical thinking. In this session, we will learn about KenKen and solve some KenKen puzzles, from beginner level on up, and then look at the math behind the math. You will even get to create your own KenKen puzzle!

4/4/17 "Liar's Bingo"

Do Bingo cards have patterns? Can you lie about what’s on your card and get away with it? Do mathematicians know something special about how to find the truth? In this session, you get to put your tall-tale skills to the test. In the process, we will learn some of the mathematics of information transmission, and how to use mathematics to find the truth.

4/4 Session Materials

5/2/17 "Spot-It!"

The rules of Spot it are simple: match a symbol on your card to a symbol on a card drawn from the top of the deck. Could this simple children’s game give rise to interesting mathematics? Is there a deeper structure to this game? In this session, we will discover how the Spot it! game is constructed and explore some of the mathematics involved.

5/2 Session Materials


Math Teacher Circle