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We'll school you in sudoku Find your grade, improve your play--and graduate to the next level. Sudoku professor Frank Longo has crafted five books with 300 sudoku each, which will take students from solving basics to super-hard, super-expert strategies. Try them and see how far you can go
If you're a beginner, or could use a little brush-up,
Sudoku U: Freshman Year is for you. Here are 300 gentle puzzles, none of which require upper-level solving techniques to conquer. Grab a pencil and give your brain a stretch.