"Review of this book" Puzzles Galore is a 96 page manuscript. Most of the puzzles are very challenging, but I had little problem with the "mini-sudokus", like 4x4, 6x6, etc. After the puzzles come "roadmaps" for finding a solution to each puzzle. Finally come the solutions to the puzzles.
"Good brain activity" This collection of puzzles includes Sudoku and other number puzzles with varying of difficulty. It includes hints and solutions to the included puzzles too. I have found people reading it often in coffee shops in Sacramento