### Solve a Sudoku

Exercise your brain (and have fun) doing Sudokus. Crayola® Dry-Erase Markers make it easy to create and solve your own fascinating puzzles.

1. Sudoku puzzles, designed in 1979 by architect and puzzle constructor Howard Garns, are popular all over the world. After you do one, you will know why. These puzzles challenge you to apply logic and reasoning, not your mathematical ability.

2. Each puzzle has only one solution. To complete any puzzle, each row (there are 9), each column (9 again), and each box of 3 x 3 cells (9 cells) must contain the numerals 1, 2, 3, 4, 5, 6, 7, 8, 9 without any repeats in a row, column, or box.

3. Each puzzle has some digits already printed in the cells. The number and placement of these clues affect the level of the puzzle’s difficulty. Use samples from a book or online to start. For a real challenge, create your own puzzles (hint: start with one that’s finished and erase several numerals).

4. Draw your Sudoku puzzle with a Crayola Dry-Erase Marker on a dry-erase board. Make 9 rows of 9 columns.

5. What is your strategy to solve a Sudoku? Some people look at the whole grid, count the numerals that appear most frequently, and fill in that numeral in each remaining column, row, and box. Others start with the 9-cell boxes (or column or row) that have the most clues and complete those first. Still other people fill each cell with all the possible numbers that would work and through a process of elimination arrive at the correct numeral for that cell. Agile puzzlers jump between rows, columns, and boxes to find the solution.

6. When you finish one puzzle, erase the board with a tissue and start another Sudoku!

Adult supervision is required for any arts & crafts project. Observe children closely and intervene as necessary to prevent potential safety problems and ensure appropriate use of arts and crafts materials. Some craft items, particularly beads and buttons, are potential choking hazards for young children. Avoid use of such small parts with children younger than 3 years. Craft items such as scissors, push pins and chenille sticks may have sharp points or edges. Avoid use of materials with sharp points by children younger than 4 years. Read all manufacturers' safety warnings before using arts and craft supplies.

• The term Sudoku comes from a Japanese phrase that translates into English as "the digits must remain single" or "numbers must occur only once." Garns’ original puzzle in New York Magazine was titled "Number Place."
• Create a template that you can reuse to make uniform puzzle grids. See the picture for an example. For one that will fill a personal-size dry-erase board, cut a 3-inch cardboard square (19.35 cm). Make one-inch (6.45 cm) marks on every side. Cut a slot at each mark. Place the template on the dry-erase board. Fill in the lines with a Dry-Erase Marker. Pick up the stencil and complete 3 boxes across and 3 down. Draw lines to complete the grid.
• Start an after-school Puzzler Club. Plan newsletters to celebrate seasons, such as puzzles around a Halloween theme.
• Puzzles for younger students could contain fewer cells and use shapes or colors instead of numerals.
• More advanced students could write algebraic equations for designing original Sudoku puzzles.
• Assessment: Ask children to design original Sudokus and devise strategies for solving each other’s puzzles. Ask them to write down the steps they used.

## Lesson Plans

##### crayola supplies
• Dry-Erase Markers
##### household supplies
• dry-erase board
• facial tissues

• Math
• Science
• Visual Arts

##### time

• Less than 1/2 hour
• Multiple Sessions

##### benefits

• Students use logical reasoning to analyze a Sudoku puzzle.

• Students self-correct their puzzle answers.

• Students solve puzzles at their levels of abilities.