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Activities Archive

Contextualizing Mathematics: Fortnite – Surviving the Storm


In this session, developed as part of the Math Circles of Inquiry project, you are playing Fortnite. There are three loot boxes marked by your teammates. Which one is the best to go to? In other words, which point is closest to a given point outside a circle, the center of the circle or one of two points of tangency connecting the outside point to the circle? The highly contextualized nature of the problem posed will make the mathematics more appealing for students to explore. Moving between individual work, partner work, and whole class discussion, students make their predictions and...

Frogs and Toads


Frogs can only move right, or down, and toads can only move left, or up. Can you exchange all the frogs and toads? Can you create a formula for the fewest number of moves? This deceptively simple puzzle starts with a row of frogs and toads, then advances to a grid. The game can be played with manipulatives, online, or even with people to provide an engaging, solitary or cooperative activity for all ages.

Function, Function, What’s Your Model?


Developed as part of the Math Circles of Inquiry project, this session is an introduction to functions. This module allows students to investigate the definition of a function, function notation, key features of a function including increasing, decreasing (in both interval and inequality notation), maximum and minimum, average rate of change and domain and range.

Materials include a full packet of worksheets pertaining to this unit (54 pages). This part of the unit (not including transforming functions) should take about six hours of class time.

Humans, Zombies, & Other Problems Crossing the River


A town has recently been plagued by an epidemic of zombies! Luckily, the virus has just started to spread and the infected are able to stave off their hunger for human brains… for now. In fact, they’re willing to work alongside the remaining humans to help them get across a river to safety. Can you get all the humans and zombies across safely?

I Walk the Line


Your regular commute begins at your house and ends at your office at the corner of 5th street and 6th avenue. You have been making this trip for years, but you are the restless (or adventurous) type, and you try to take a different route each day. At some point, you start to wonder how long it will take you to try all of the routes.

Oh, did I mention that you have to avoid the zombies?

Investigating the Surface Area of Prisms


Developed as part of the Math Circles of Inquiry project, this module enables students to build understanding about surface area. Students will complete three tasks dealing with surface area and volume of rectangular and triangular prisms, including a real world investigation, presented in Three Acts. The tasks will go from the concrete to the abstract as students gain understanding of what it really means to calculate surface area and volume. The module includes a refresher on area and perimeter.

One-Player Games


Here is a collection of seven one player games, and one two player game. Your goal in each game is to find the winning strategy. As the rules change, can you still win? Various mathematical strategies can be employed, including working backwards, problem posing, invariants, and parity. Each game can be explored alone or in sets, providing material for several circle sessions or the classroom.

Practical Probability: Casino Odds and Sucker Bets


Gambling casinos are there to make money, so in almost every instance, the games you can bet on will, in the long run, make money for the casino. However, to make people gamble, it is to the casino’s advantage to make the bets appear to be “fair bets,” or even advantageous to the gambler. Similarly, “sucker bets” are propositions that look advantageous to one person but are really biased in favor of the other. In this article, we’ll examine what is meant by a fair or biased bet, and we will look in detail at some casino games and sucker...

Supreme Court Handshakes


Developed as part of the Math Circles of Inquiry project, this session is a good introduction to the 8th grade or Algebra Math curriculum using inquiry based instruction. Students are asked to use their problem solving skills in order to determine the relationship between the number of Supreme Court justices and handshakes that occur when each pair shakes hands exactly once. Students will begin exploring with simpler numbers and work up to creating an algebraic expression to represent the function. This lesson allows for multiple representations by using a table, list, circle diagram, matrix and manipulatives.

The Jug Band


“Using just that 5 pint jug and that there 12 pint jug, measure me 1 pint of water!” Is this possible with just the two jugs? What about a 7 pint jug and 17 pint jug? Or p pint and q pint jugs?

Tic-Tac-Toe 2.0: New Takes on an Old Classic


The game of Tic-Tac-Toe has roots going back centuries. Grid-style game boards have been found in Ancient Egypt, during the Roman Empire, and in our current age on restaurant placemats. Multiple avenues of exploration are possible with this simple children’s game. A related game called “Gobblet Gobblers” takes Tic-Tac-Toe to a whole new level!

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