Sudoku U: Sophomore Year

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 ready to move on and build your skills, then Frank Longo has 300 medium sudoku to try.  Start with the easier ones and work your way up.