| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2016 | The New Year Challenge | Algebra |
| January 2016 | The 10 Tallest Monuments | Algebra, Logic |
| January 2016 | 2016 Puzzle | Logic |
| February 2016 | Math Odd Letter Out | Logic |
| February 2016 | Four on the Floor | Logic |
| February 2016 | Three Digit Number problem | Logic, Arithmetic |
| March 2016 | The 10 Square Rectangle | Algebra |
| March 2016 | Tic-Tac-Logic | Logic |
| March 2016 | Monkey Business | Logic |
| April 2016 | How Sweet It Is! | Algebra |
| April 2016 | Futoshiki | Logic, Arithmetic |
| April 2016 | Math Art | Logic |
| May 2016 | Inheritance Problem | Algebra |
| May 2016 | The Square Problem | Algebra |
| May 2016 | Cylindrical Fuel Tank Problem | Algebra, Geometry, or Calculus |
| June 2016 | Six Mix | Arithmetic, Logic |
| June 2016 | A Whole Lot in Common | Logic |
| June 2016 | Weighted Diagonal | Logic |
| July 2016 | Nine Digit Number | Logic |
| July 2016 | The Missing Link | Logic, Arithmetic |
| July 2016 | Three Texas Drovers | Algebra |
| August 2016 | The Milkman's Puzzle | Logic |
| August 2016 | Chess Problem (Revisited) | Logic |
| August 2016 | Which Barrel was left? | Logic, Arithemtic |
| September 2016 | The 9 Square Rectangle | Algebra |
| September 2016 | 10-Digit Number Problem | Logic |
| September 2016 | The Tower of London (Part 1) | Logic |
| October 2016 | The Leaning Tower of Pisa | Algebra |
| October 2016 | How Old is Pocahontas? | Algebra |
| October 2016 | Against the Wind | Algebra |
| November 2016 | The Tower of London (Part 2) | Logic |
| November 2016 | The Hat that Didn't Sell | Logic |
| November 2016 | Thanksgiving Crossword Puzzle | Logic |
| December 2016 | Sierpinski's Christmas Tree | Algebra |
| December 2016 | Christmas Present Puzzle | Algebra |
| December 2016 | Christmas Tree Puzzle | Algebra |
| December 2016 | Christmas Bonus -- The Pleacher Family Christmas | Logic |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2017 | The New Year Challenge | Algebra |
| January 2017 | Math Before Breakfast | Algebra |
| January 2017 | Year Without Brackets | Algebra |
| February 2017 | The Telephone Number | Algebra |
| February 2017 | Cowboy Puzzler | Algebra |
| February 2017 | A Painted House | Algebra |
| March 2017 | String Problem | Algebra |
| March 2017 | Rectangular Parallelepiped Problem | Algebra, Geometry |
| March 2017 | Street Closure Problem | Logic |
| April 2017 | Lock Problem | Logic |
| April 2017 | Area Problem | Algebra, Geometry |
| April 2017 | Clock Problem | Logic |
| May 2017 | Three Walkers | Algebra |
| May 2017 | College Math | Algebra |
| May 2017 | The Three Thieves | Algebra |
| June 2017 | As Easy As A, B, ... | Arithmetic |
| June 2017 | The Three Thieves (Part 2) | Algebra |
| June 2017 | The Lock Problem (Part 2) | Algebra |
| July 2017 | Prime Time | Arithmetic, Logic |
| July 2017 | CalcuDoku | Algebra |
| July 2017 | Game Devisers | Logic |
| August 2017 | Balanced Equations | Algebra, Logic |
| August 2017 | Cinematic Conversions | Logic, Arithmetic |
| August 2017 | Petite Circle-Sum Walkthrough | Logic, Arithmetic |
| September 2017 | Mr. P's Grandchildren | Algebra |
| September 2017 | NFL Wackie Wordies | Logic |
| September 2017 | A Radical Equation | Algebra |
| October 2017 | Generosity after the Hurricanes | Arithmetic, Algebra |
| October 2017 | Russian Army motorcyclists | Geometry |
| October 2017 | Another A and B problem | Algebra |
| November 2017 | Addition Problem | Logic, Arithmetic |
| November 2017 | Picture Magic Square | Logic, Algebra |
| November 2017 | Blowin' in the Wind | Algebra |
| December 2017 | Christmas Tree Puzzle | Algebra |
| December 2017 | Math Art | Logic |
| December 2017 | Meet 16 | Algebra |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2018 | The New Year Challenge | Algebra |
| January 2018 | New Year Magic Square | Logic, Arithmetic |
| January 2018 | 2018 Multiplication Problem | Logic, Arithmetic |
| February 2018 | David Jones' Locker | Logic, Arithmetic |
| February 2018 | Two-Player Game | Logic, Arithmetic |
| February 2018 | De Morgan's Age Problem | Logic, Arithmetic |
| March 2018 | Super Bowl Party Game | Logic, Arithmetic |
| March 2018 | Women's Basketball Polls | Logic, Arithmetic |
| March 2018 | Moving Walkways | Logic |
| April 2018 | April Fools | Logic, Arithmetic |
| April 2018 | Cross Number Puzzle | Logic, Arithmetic |
| April 2018 | Top Ten Colleges | Logic |
| May 2018 | Isosceles Triangle Problem | Algebra |
| May 2018 | Math Scramble | Logic |
| May 2018 | World Tour | Logic |
| June 2018 | As Easy As A + B + C | Algebra |
| June 2018 | As Easy As Pi | Algebra |
| June 2018 | Skyscrapers | Logic |
| July 2018 | Distance Problem | Geometry |
| July 2018 | Loco Sudoku | Logic |
| July 2018 | Dividing the Spoils | Algebra |
| August 2018 | Cross Math Puzzle | Algebra, Logic |
| August 2018 | What Fraction? | Geometry |
| August 2018 | Three Lighthouses | Logic |
| September 2018 | Mr. P's Phone Number | Arithmetic, Logic |
| September 2018 | MOD Pizza | Algebra, Geometry |
| September 2018 | Geometric Shapes Search | Geometry |
| October 2018 | Missing Mathematicians | Logic |
| October 2018 | The 416 Fire | Arithmetic, Logic |
| October 2018 | Chess Puzzler (5 pieces) | Logic |
| November 2018 | Four Digit Number Trick | Arithmetic, Logic |
| November 2018 | SUMOKU | Arithmetic, Logic |
| November 2018 | Change for a (half) Dollar | Arithmetic, Logic |
| December 2018 | Christmas Tree Puzzle | Algebra |
| December 2018 | Mince Pies | Logic |
| December 2018 | Sum and Product | Algebra |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2019 | The New Year Challenge | Algebra |
| January 2019 | Chess Puzzler (8 Queens) | Logic |
| January 2019 | Boeing 747 | Arithmetic |
| February 2019 | Bucket Problem | Arithmetic, Logic |
| February 2019 | Stewart's Birthday Cake | Geometry, Algebra |
| February 2019 | Math Doublets | Logic |
| March 2019 | Elephant Drinking Problem | Arithmetic |
| March 2019 | Jersey Pi Problem | Logic |
| March 2019 | Scrabble Squares | Arithmetic, Logic |
| April 2019 | Laying Eggs | Logic |
| April 2019 | Easter Word Cross | Logic |
| April 2019 | Easy as 1, 2, 3! | Algebra |
| May 2019 | Bucket Problem #2 | Geometry |
| May 2019 | Trading in the Philippines | Arithmetic, Logic |
| May 2019 | Longfellow's Bees | Algebra |
| June 2019 | Family Age Problem | Algebra |
| June 2019 | The monk and the bridges | Logic |
| June 2019 | TV Viewing Distance | Algebra, Geometry |
| July 2019 | Dividing Apples | Logic |
| July 2019 | Money Problems | Algebra |
| July 2019 | Prison Problem | Logic |
| August 2019 | Insulin Pen | Logic |
| August 2019 | Fill in the Squares | Logic |
| August 2019 | The Envelope Problem | Logic, Arithmetic |
| September 2019 | NFL Passer Rating | Algebra |
| September 2019 | Dice Roulette | Probability |
| September 2019 | Easy as 1, 2, 3! | Algebra |
| September 2019 | Corporate Greed in America | Arithmetic |
| October 2019 | How Old is the Boss? | Algebra |
| October 2019 | The Spider and the Fly | Geometry |
| October 2019 | Skyscrapers Part 2 | Logic |
| November 2019 | The Rocky Mountain Lobos | Algebra |
| November 2019 | Prime Choices | Logic, Arithmetic |
| November 2019 | Number Trick | Algebra |
| December 2019 | Christmas Tree Puzzle | Algebra |
| December 2019 | As Easy as A, B, and C | Algebra |
| December 2019 | Kopek Problem | Logic |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2020 | The New Year Challenge | Algebra |
| January 2020 | Mathematical Roundabouts | Logic |
| January 2020 | The Odometer Puzzle | Algebra |
| February 2020 | Train Meeting | Algebra |
| February 2020 | Decoding Messages | Logic |
| February 2020 | C.S.U. Volleyball | Algebra |
| February 2020 | Mass Shootings in 2019 | Arithmetic |
| March 2020 | Food Bank Truck | Algebra |
| March 2020 | Calculus Tag-A-Long | Calculus, Logic |
| March 2020 | Test Problems | Algebra |
| April 2020 | Letter By Letter | Logic |
| April 2020 | Math Fill Ins | Logic, Math Definitions |
| April 2020 | Coronavirus in Colorado | Algebra, Precalculus |
| May 2020 | Parking Problem | Algebra |
| May 2020 | Pentagon Problem | Geometry |
| May 2020 | Getting from A to B | Logic |
| June 2020 | Different Rectangles #1 | Logic |
| June 2020 | Numbrix | Logic |
| June 2020 | 8 Easy Equations | Algebra |
| July 2020 | Different Rectangles #2 | Logic |
| July 2020 | Arby's Coupons | Logic |
| July 2020 | SUM-THING MISSING | Logic |
| August 2020 | Different Rectangles #3 | Logic |
| August 2020 | The Prayer Circle Problem | Geometry, Trigonometry |
| August 2020 | How Many Pages? | Logic, Arithmetic |
| September 2020 | Presidential Golf | Arithmetic |
| September 2020 | Dividing the Meal | Logic, Arithmetic |
| September 2020 | Numbers Puzzle | Logic, Arithmetic |
| September 2020 | A Biblical Treasure Hunt | Algebra, Geometry, Trig, Logic |
| October 2020 | Five Digits | Logic, Arithmetic |
| October 2020 | Smallest Integer | Logic, Algebra |
| October 2020 | Hiroimono | Logic |
| October 2020 | Trump's False Statements | Algebra |
| November 2020 | Filling A Cistern | Algebra |
| November 2020 | Your (Math) Word Against Mine | Logic |
| November 2020 | Political Arithmetic | Algebra |
| November 2020 | RR Bridge Part 1 | Logic, Prealgebra |
| December 2020 | Holiday Trip | Logic |
| December 2020 | Wrapping Paper Problem | Calculus |
| December 2020 | Decode a message | Logic, Magic Squares |
| December 2020 | RR Bridge Part 2 | Algebra |
| December 2020 | A Christmas Message | Algebra |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2021 | The New Year Challenge | Logic, Algebra |
| January 2021 | Interesting Sums | Logic |
| January 2021 | Knight Life | Logic, Chess |
| January 2021 | Pythagorean Theorem Days | Logic, Geometry |
| January 2021 | A problem from Bhaskara's Lilavati | Algebra |
| February 2021 | Hiroimono Part 2 | Logic |
| February 2021 | Math Boggle | Logic |
| February 2021 | NBA Playoff | Logic, Algebra |
| February 2021 | Prime Clock | Logic, Algebra |
| March 2021 | Pie Thoughts | Logic |
| March 2021 | Chess Problem | Statistics |
| March 2021 | Arithmetic Sequences | Algebra, Logic |
| March 2021 | Magic Circles | Logic |
| April 2021 | Pool Problem | Geometry |
| April 2021 | COVID-19 Deaths | Arithmetic |
| April 2021 | Easter Egg Hunt | Logic |
| April 2021 | Place Setting Problem | Algebra |
| April 2021 | Snowtime in Colorado | Algebra, Geometry |
| May 2021 | Friends in Far Places | Logic |
| May 2021 | Go Jump in the Lake | Geometry |
| May 2021 | Sequence Problem | Algebra |
| May 2021 | Geometry Problem | Geometry |
| June 2021 | Apartments | Logic |
| June 2021 | Mr. P and his grandson | Logic |
| June 2021 | Big Number Problem | Logic |
| June 2021 | Consecutive Fibonacci Numbers | Algebra |
| June 2021 | Sooley Problem | Algebra |
| July 2021 | Dots in a grid | Geometry |
| July 2021 | Money Problem | Algebra |
| July 2021 | Oxford Problem | Algebra |
| July 2021 | Trains | Logic |
| August 2021 | Carpenty Problem | Logic, Algebra |
| August 2021 | Mystery Numbers | Logic |
| August 2021 | Triangle Problem | Logic, Geometry, Calculus |
| August 2021 | Inner Circles | Logic |
| September 2021 | Circle Problem | Geometry |
| September 2021 | Square Problem | Algebra, Geometry |
| September 2021 | Egg Problem | Algebra |
| September 2021 | Window Problem | Algebra, Geometry |
| October 2021 | What's the Angle? | Geometry |
| October 2021 | Travel Problem | Algebra |
| October 2021 | Was It A Cat I Saw? | Logic |
| October 2021 | Cross Math Puzzle | Logic, Arithmetic |
| November 2021 | Math Blocks | Logic |
| November 2021 | Blackjack Balancing Act | Logic, Algebra |
| November 2021 | Tiling Problem | Algebra, Geometry |
| November 2021 | Too Many Choices | Algebra |
| December 2021 | Christmas Message | Algebra |
| December 2021 | Carom Billiard Table | Algebra, Logic |
| December 2021 | The Smaller Number | Algebra |
| December 2021 | Christmas Word Cross | Logic |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2022 | The New Year Challenge | Logic, Algebra |
| January 2022 | Incenter of a Triangle | Geometry |
| January 2022 | Square Routes | Logic |
| January 2022 | 1876 M.I.T. Exam question | Algebra |
| February 2022 | Math Blocks Part 2 | Logic |
| February 2022 | Pepper Problem | Logic, Algebra |
| February 2022 | Truth Tellers and Liars | Logic |
| February 2022 | Tile Problem | Geometry, Algebra |
| March 2022 | Venn Diagram Mystery | Logic |
| March 2022 | Dirty Dozen Balancing Act | Logic, Algebra |
| March 2022 | Number Problem | Algebra |
| March 2022 | Celebrations in India | Logic |
| April 2022 | Rectangle Problem | Algebra, Geometry |
| April 2022 | Cable Search | Logic |
| April 2022 | Magic Hexagon | Logic, Arithmetic |
| April 2022 | Digits Problem from 1915 | Algebra |
| May 2022 | Square Root Problem | Algebra |
| May 2022 | Magic Square | Algebra |
| May 2022 | Tic Tac Toe -- Math Style | Logic |
| May 2022 | Goat Grazing by Gazebo | Geometry, Trigonometry |
| June 2022 | Time the Two Skaters | Algebra |
| June 2022 | Alphabetical Numbers | Logic |
| June 2022 | Divisible by 7 | Algebra |
| June 2022 | Ladder Problem | Geometry |
| July 2022 | The Tortoise and the Hare | Algebra |
| July 2022 | Banneker's Cattle Problem | Algebra |
| July 2022 | Jean and Jane | Logic |
| July 2022 | July 4th Parade | Logic |
| July 2023 | Locker Problem | Algebra, Logic |
| August 2022 | OSLO | Logic |
| August 2022 | Fill the Bucket | Algebra |
| August 2022 | Triangle Problem | Geometry |
| August 2022 | Cat and Turtle on a Table | Algebra |
| September 2022 | FoCo Traffic Problem | Logic |
| September 2022 | Ten Circles in a "Pyramid" | Geometry |
| September 2022 | Bat and Ball | Algebra |
| September 2022 | Goal Post Multiplication | Arithmetic, Logic |
| October 2022 | Cross Math Puzzle | Logic, Arithmetic |
| October 2022 | Zero Power | Algebra |
| October 2022 | Hot Air Balloon | Geometry |
| October 2022 | Pumpkin Patch Problem | Geometry, Algebra |
| November 2022 | Basketball Problem | Logic, Arithmetic |
| November 2022 | Carol Pleacher | Algebra |
| November 2022 | Mean / Median | Algebra |
| November 2022 | Number Cross Sums | Logic |
| December 2022 | Sum Christmas Trees | Logic, Arithmetic, Algebra |
| December 2022 | The Island People | Logic |
| December 2022 | 1,000 Lamps | Logic, Algebra |
| December 2022 | FORTY + FIFTY + ZERO + ZERO = NINETY | Logic, Algebra |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2023 | The New Year Challenge | Logic, Algebra |
| January 2023 | Minimum Wage | Arithmetic |
| January 2023 | MYTH: MATH IS HARD | Arithmetic, Logic |
| January 2023 | Bicycle Helmets | Probability |
| February 2023 | Mean, Median, Mode | Arithmetic, Logic, Statistics |
| February 2023 | Four Cars | Algebra, Logic |
| February 2023 | Book Problem | Algebra, Logic |
| February 2023 | The number 201 | Algebra, Logic |
| March 2023 | Pie Eaters | Algebra |
| March 2023 | Green Eggs and Ham | Arithmetic, Logic |
| March 2023 | Number Cross Sums | Arithmetic, Logic |
| March 2023 | Mathematical Wackie Wordies | Logic |
| April 2023 | Return of the Island People | Logic |
| April 2023 | Pen Problem | Algebra |
| April 2023 | Three zeros | Logic, Arithmetic |
| April 2023 | How Many Oranges? | Logic, Algebra |
| May 2023 | World Cup Soccer | Logic |
| May 2023 | Digit Problem | Algebra, Logic |
| May 2023 | Locker Problem | Algebra, Logic |
| May 2023 | 47 Counters | Algebra, Logic |
| June 2023 | How far did Jonah drive? | Algebra |
| June 2023 | 31 Students | Logic |
| June 2023 | Window Problem | Arithmetic |
| June 2023 | Box in a sphere | Geometry |
| July 2023 | Book Problem | Algebra |
| July 2023 | Ordered Triples Problem | Algebra |
| July 2023 | Circle Problem | Geometry |
| July 2023 | Locker Problem | Algebra, Logic |
| August 2023 | Hidden Math Words | Logic |
| August 2023 | Painted Cube Problem | Geometry |
| August 2023 | Magic Square | Algebra |
| August 2023 | Whose sum is correct? | Algebra |
| September 2023 | Daffy Definitions | Logic |
| September 2023 | Trapezoidal Problem | Geometry |
| September 2023 | Mr. P Problem | Logic |
| September 2023 | The Girard And de Marco Families | Logic |
| October 2023 | Odd Letter Out | Logic |
| October 2023 | Hex Path | Logic |
| October 2023 | Mailbox Numbers | Logic |
| October 2023 | How Old are the Daughters? | Logic |
| November 2023 | Bo, Jo, Mo, and Flo | Algebra |
| November 2023 | Weight Loss Problem | Algebra |
| November 2023 | What's My Number? | Logic |
| November 2023 | Company Gift | Algebra |
| December 2023 | Christmas Phobias | Logic |
| December 2023 | Christmas Wackie Wordies | Logic |
| December 2023 | Sum More Christmas Trees | Arithmetic, Logic |
| December 2023 | Who is leading Santa's Sleigh? | Logic |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2024 | The New Year Challenge | Logic, Algebra |
| January 2024 | Mid Loop | Logic |
| January 2024 | 2004 Super Bowl | Logic, Arithmetic |
| January 2024 | Golf with Tiger Woods | Algebra II |
| February 2024 | Chess Tournament | Logic, Probability |
| February 2024 | Washington Monument Baseball Problem | Calculus |
| February 2024 | Ten Mile Hike | Algebra II |
| February 2024 | Lucky Numbers | Logic |
| March 2024 | Pi Problem | Logic |
| March 2024 | Circle Problem | Algebra |
| March 2024 | Logarithm Problem | Algebra II |
| March 2024 | Puzzle Shop Puzzle | Logic |
| April 2024 | Six Coins, Three Ways | Logic, Arithmetic |
| April 2024 | 4 x 4 Square | Logic |
| April 2024 | How Far Can You See? | Geometry |
| April 2024 | Who Am I? | Logic, Arithmetic |
| May 2024 | Can you break the code? | Logic, Arithmetic |
| May 2024 | Center of a cube | Geometry |
| May 2024 | The Fantastic Formula | Algebra |
| May 2024 | Horses and Chickens | Algebra or logic |
| June 2024 | Colorado Temperature Change | Algebra |
| June 2024 | Five Numbers | Algebra |
| June 2024 | From American Somoa to Fiji | Logic |
| June 2024 | Knights and Liars | Logic |
| July 2024 | SUM Things to ponder | Logic, Arithmetic |
| July 2024 | Pretzel Problem | Logic, Algebra |
| July 2024 | Tetrahedron Problem | Geometry, Algebra |
| July 2024 | Where do the Magicians Rank? | Logic |
| August 2024 | Special Birthday Card | Algebra |
| August 2024 | Which Way to Jubilee? | Logic |
| August 2024 | Prime Time Soccer | Logic, Arithmetic |
| August 2024 | Boxes of Red and Blue Balls | Logic, Arithmetic |
| September 2024 | Cleaning up the Yard | Algebra, Logic |
| September 2024 | Midnight and Mr. P | Algebra, Logic |
| September 2024 | Soccer Standings | Logic |
| September 2024 | Tom, Dick, and Harry | Logic |
| October 2024 | Math Path | Arithmetic, Logic |
| October 2024 | How Tall is That? | Arithmetic |
| October 2024 | Olympic Games | Logic |
| October 2024 | Another Chicken Nuggets Problem | Logic, Arithmetic |
| November 2024 | Dave and Carol | Logic |
| November 2024 | Urim and Thummim | Probability |
| November 2024 | No Hunting! | Geometry |
| November 2024 | Sequence Problem | Algebra |
| December 2024 | Sum Christmas Trees | Logic, Algebra |
| December 2024 | Regions in a Circle | Geometry |
| December 2024 | The Devil and Daniel Webster | Arithmetic |
| December 2024 | The Diamond Tree Challenge | Logic |
| Date | Name of Problem of the Month | Math Needed |
|---|---|---|
| January 2025 | The New Year Challenge | Logic, Algebra |
| January 2025 | Elvis Presley | Logic, Algebra |
| January 2025 | Elvis Presley Portrait | Logic |
| March 2025 | Pi Problem | Logic |