A fun book to spend time and stimulate your brain. Although most problems in this book are super easy, there are some that will challenge you a little bit and will steal a few minutes of your time to solve them.
I highly recommend this book for high school students, math enthusiasts and the international students, who are trying to attend and science school in an English speaking country.
In a nutshell, it is a great replacement for TV. Get one, and enjoy your life.