K-12 Math Puzzles from the Math Forum

Back to Math Problems, Puzzles, Tips & Tricks

Math Forum Year Game
facilitated by Max Ray-Riek, Judy Ann Brown (2003-1998) and Ruth Carver (1997-1996)

2016 Puzzle |  View Solutions From Past Years
Note: To view solutions from 1996 - 2015, use the link above to our automated page. Select Year and Solution For. Click Find to display previously submitted solutions.

Note: To view archived pages from 1996 - 2003, use these links to the individual pages:
2003 Puzzle |  2002 Puzzle |  2001 Puzzle |  2000 Puzzle |  1999 Puzzle |  1998 Puzzle
1997 Puzzle |  1996 Puzzle

All the King's Digits - Terry Trotter

Challenge: Using the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9, and the operations of +, -, x, ÷, sqrt (square root), cbrt (cube root), ^ (raise to a power), and ! (factorial), along with grouping symbols, write expressions for the counting number 100.

Four 4's Puzzle - Ruth Carver

Challenge: Using four 4's and any operations, try to write equations that have the numbers from 0 to 100 as the answer.

Math Line Puzzles

Can you connect the dots in a 3x3 grid using 4 straight lines?

Can you figure out how to plant 7 rosebushes so that they form 6 straight lines with 3 rosebushes in each line? Or 10 bushes in 5 lines with 4 in each? How about 19 in 9 lines with 5 in each?

Can you construct 9 triangles by drawing 3 straight lines through a capital M?

Can you move exactly two toothpicks to form four 1x1 squares?

Critical Thinking Puzzles

A selection of brain teasers from Michael DiSpezio's new book, Critical Thinking Puzzles. Five puzzles, with solutions: Pyramid Passage, Spare My Brain, Putting It Together, Fractured Farmland, Kitchen Cups.