## Puzzles, Games, and Recreational Math

This is nowhere close to a complete list! There's so much fun stuff out there!

SolveMe Mobiles Puzzles: Sometimes you get information on total weights, and you can always assume the mobile is balanced if it's not tilted. In general, the higher the number, the harder they are to solve.

SolveMe Who Am I?: Identify the number based on the clues. (Warning: at the time of this writing, #18 is impossible!)

BrainBashers Puzzles: BrainBashers has many different challenging puzzles made by Kevin Stone, who lives in a village in England. Kevin has had a love of puzzles since a very early age and he started to write puzzles when he was twelve.

NRICH Enriching Mathematics: Lower secondary is probably the most appropriate level here.

KenKen: Includes various difficulty levels. Great practice for thinking about numbers (especially factoring) and logic!

Kakuro (aka Cross Sums): Fill in digits to add up to the specified number, using each only once. For instance, if two digits must sum to 17, they must be 8 and 9 (in either order).

Futoshiki (aka Unequal): Fill in digits to meet the criteria, which include inequalities (< and > statements).

Numbrix: Another neat logic puzzle. Try the easier levels first to get the hang of it.

Sudoku: Use logic to enter the numbers 1-9 once each in every row, column, and box. This site lets you set the difficulty level.

Battleship: logic/strategy puzzle. Difficulty level may vary from day to day. Be sure to click on information (i) and Help.

Brain Teasers from the National Council of Teachers of Mathematics' Illuminations website

Petals Around the Rose: Figure out the rule for the score from a roll of 5 dice... but if you do, no telling anyone else who hasn't solved it! (Ms. Wright knows it. You can brag to her.) You can read the story about Bill Gates without spoiling the puzzle.

Maths Resources (the British call it maths): Good math challenges include 24, Number Wang (weird British joke), and Mathman. This site has dozens of fun puzzles and games, including classic card and board games as well as newer online games like 2048. Unfortunately they don't often include the rules!

Parallel Project by Simon Singh: Another British site, designed for 11-to 13-year-olds to highlight fascinating math that probably isn't taught in schools (such as how you could topple the Empire State Building with dominoes). You need to sign up for this one, but it's non-commercial.

Calculation Nation online math games (also from NCTM)

Hotmath math games are at various levels; pick one that is appropriate for you (the cockroach one is pretty funny)

Vi Hart has a lot of amazing videos on YouTube. I haven't watched all of these, and some rely on high school or college math.

Lure of the Labyrinth is a computer game designed for pre-algebra middle schoolers. It has a storyline in which you are rescuing a lost pet from monsters in a labyrinth by solving complicated math puzzles. You can set up a free account to try it. I have not investigated it much yet. If you try it, let me know what you think of it!

Lewis Carroll Puzzles: How can you go wrong? I also strongly recommend reading Alice in Wonderland and Through the Looking Glass if you have not already!

SolveMe Mobiles Puzzles: Sometimes you get information on total weights, and you can always assume the mobile is balanced if it's not tilted. In general, the higher the number, the harder they are to solve.

SolveMe Who Am I?: Identify the number based on the clues. (Warning: at the time of this writing, #18 is impossible!)

BrainBashers Puzzles: BrainBashers has many different challenging puzzles made by Kevin Stone, who lives in a village in England. Kevin has had a love of puzzles since a very early age and he started to write puzzles when he was twelve.

NRICH Enriching Mathematics: Lower secondary is probably the most appropriate level here.

KenKen: Includes various difficulty levels. Great practice for thinking about numbers (especially factoring) and logic!

Kakuro (aka Cross Sums): Fill in digits to add up to the specified number, using each only once. For instance, if two digits must sum to 17, they must be 8 and 9 (in either order).

Futoshiki (aka Unequal): Fill in digits to meet the criteria, which include inequalities (< and > statements).

Numbrix: Another neat logic puzzle. Try the easier levels first to get the hang of it.

Sudoku: Use logic to enter the numbers 1-9 once each in every row, column, and box. This site lets you set the difficulty level.

Battleship: logic/strategy puzzle. Difficulty level may vary from day to day. Be sure to click on information (i) and Help.

Brain Teasers from the National Council of Teachers of Mathematics' Illuminations website

Petals Around the Rose: Figure out the rule for the score from a roll of 5 dice... but if you do, no telling anyone else who hasn't solved it! (Ms. Wright knows it. You can brag to her.) You can read the story about Bill Gates without spoiling the puzzle.

Maths Resources (the British call it maths): Good math challenges include 24, Number Wang (weird British joke), and Mathman. This site has dozens of fun puzzles and games, including classic card and board games as well as newer online games like 2048. Unfortunately they don't often include the rules!

Parallel Project by Simon Singh: Another British site, designed for 11-to 13-year-olds to highlight fascinating math that probably isn't taught in schools (such as how you could topple the Empire State Building with dominoes). You need to sign up for this one, but it's non-commercial.

Calculation Nation online math games (also from NCTM)

Hotmath math games are at various levels; pick one that is appropriate for you (the cockroach one is pretty funny)

Vi Hart has a lot of amazing videos on YouTube. I haven't watched all of these, and some rely on high school or college math.

Lure of the Labyrinth is a computer game designed for pre-algebra middle schoolers. It has a storyline in which you are rescuing a lost pet from monsters in a labyrinth by solving complicated math puzzles. You can set up a free account to try it. I have not investigated it much yet. If you try it, let me know what you think of it!

Lewis Carroll Puzzles: How can you go wrong? I also strongly recommend reading Alice in Wonderland and Through the Looking Glass if you have not already!