This is not a textbook. It is not a contest booklet. It is not a set of lessons for
classroom instructIOn. It does not give a series of projects for students, nor does it
offer a development of parts of mathematics for self-instruction.
So what kind of book is this? It is a book produced by a remarkabl~ cultural
circumstance, which fostere~ the creation of groups of students, teachers, and
mathematicians, called mathematical circles; in the former Soviet Union. It is
predicated on the idea that studying mathematics can generate the same enthusiasm
as playing a tearn sport,_ without necessarily being competitive.