I had bought the following 2 books from the author.
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I am sure later I will buy more for the upper primary levels when my son reaches that stage. There are samples in the publisher's link . However, let me share 3 pages from the Junior 1 book (Primary 1-2) for reporting purpose to illustrate better about the quality of those questions provided in the book.
Sample 1:
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Most children at age 7-8 can tell the time, but they need to think to calculate hours and minutes. Yes, they can do it!
Sample 2 :
Another problem question.. I was surprised that my son can do this.. without using algebra or the "standard" method that I learned in secondary school. He "drew" 110 circles and divide them to get the answer!
Sample 3 :
A systematic approach for 7-8 years old to count..the kids need to "visualize" those hidden cube!
I believe the above questions shows the "true color" of the book. Those questions may be more challenging questions, I admit, but manageable.
My intention is not to prepare my son for any competition. Rather, I use this book to encourage him to think, to analyze and to solve the questions. During my school time, I practiced mathematics like robot.. My teachers always said, "practice makes perfect".. yeah, I practiced up to hundred over equations per day (many students at that time did that). But I would say, I memorized the trick, rather than to think and understand the skill. I suffered in university. Well, some people still feel proud of those "traditional Chinese school" method. For me, I prefer something different. I don't want my son to lose interest solving hundreds of questions per day. This book is the solution to my problem!
In fact, my son loves solving those questions. Some times he may get frustrated when he does not know the answer. But with a little bit of coaching and encouragement, he is on his way... If you think that you are not good in math, don't worry, answer is given at the back of the book!