This book contains 100 puzzles that you can enjoy. 
It also teaches you the steps in problem solving:

1.      Look at the goal - observe the special features
2.      Know your inputs, resources or capabilities
3.      Start with what you know first
4.      Try to solve half the problem - it is your foundation
5.      Take your time to solve the remainder. Ask for help.

The various shapes in this puzzle trains you in the skill of problem solving and give you the confidence that you know what to do. With this self-confidence, you can approach any problem in your daily life.