The books (Volumes 1 to 5) are based the lecture notes from our 2015 Mathcounts State Competition Training Program. We have reviewed the manuscripts carefully and some of our students also helped. Please email us at mymathcounts@gmail.com if you see any typos or mistakes or you have a different solution to any of the problems in the book. We really appreciate your help in improving the books. This book can be used by 5th to 8th grade students preparing for Mathcounts State and National Competitions.
Each chapter consists of (1) basic skill and knowledge section with plenty of examples, (2) exercise problems, and (3) detailed solutions to all problems.
Volume 4:
http: //www.amazon.com/Mathcounts-State-Competition-Preparation-4/dp/1505283493
Volume 5:
http: //www.amazon.com/Mathcounts-State-Competition-Preparation-5/dp/1505241413