The program used is called MathQuest 3, and it is an especially interesting program for young children because its approach to learning involves many types of activities and hands-on experiences.  It uses the textbook called MathQuest 3, 1986 edition, Addison-Wesley Publishers Limited (ISBN-10: 0-201-19300-0 or ISBN-13: 978-0-201-19300-8).
The old Chinese proverb, below, explains MathQuest's approach to learning:
I hear and forget
I see and I remember
I do and I understand.
The Mathematics 3 program aims to make learning fun for students so they will like mathematics.  Each assignment is designed so that it provides valuable learning experiences.
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