When it comes to easiest Sudoku type, no other Sudoku type can beat Trio Sudoku. In the Trio Sudoku, similar to Even Odd Sudoku, it is divided into three parts. Each of these parts can be solved independently. So difficult level of this Sudoku is 1/3rd of the Classic Sudoku. Kids love to solve this Sudoku type and this is one of the best Sudoku type to introduce kids to Sudoku variations. I have created many Trio Sudoku puzzles for not only kids but some Trio Sudoku variations for experienced Sudoku players too. I have posted some of these Sudoku puzzles and many of these puzzles, still needs to be published. This is the reference page which I will be using to give reference to all these Trio Sudoku puzzles
Rules of Trio Sudoku
Classic Sudoku Rules apply. Additionally cells with circles must contain the digits 1, 2 and 3. Cells with squares must contain the 4, 5 and 6. Blank cells must contain the digits 7, 8 and 9.
Here is list of Trio Sudoku puzzles
Trio Sudoku Variations
Rules of Trio Sudoku Variation is given at the below links