I like the book - think "AOPS, but different in several respects". (I quickly looked on amazon which shows much of the book.)
Among many good examples:
- p. 26: "put in some addition and subtraction to make round numbers"
- p. 207: "which is bigger: 87/437 or 85/435?" ("funny subtraction").
The author's description above is correct:
... alternative to moving ahead to do math with a higher grade.
... grade-level math in greater depth and cover other things that they'll never see in school. I ask much harder questions to try to build problem solving skills and try to make math fun.
"Hard Math for Middle School: IMLEM Plus Edition" by the same author also looks good.
(The "middle school" book is probably more competition-oriented, while the "elementary school" book is more like "a must know, solid elementary math".)
