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! You're almost ready to graduate! If you're looking for very hard puzzles, you'll find them in Sudoku U: Senior Year. Every one of these 300 logical conundrums requires upper-level solving techniques.
