The checking of subtraction and division problems is discussed. (DT)

A method for compound subtraction which avoids the need to memorize a difficult set of subtraction facts is explained. (DT)

A proposal is made that teachers integrate the various forms of the four operations of addition, subtraction, multiplication, and division in a concrete way, rather than teaching the topics sequentially. (DT)

A distinction is made between an algorithm and the justification for the algorithm. Examples of both are given for the operations with whole numbers. (DT)

A theorem on divisibility in decimal and non-decimal numeration systems is developed; its use in a series of discovery-centered lessons is suggested. (DT)

The authors suggest how the patterns in the digits in the multiplication tables may be exploited in the classroom. (MM)

A history of perfect numbers is presented, which briefly covers the 27 values known at this time. (MP)

Presents evidence that human infants possess a mechanism for determining and representing small numbers of entities and procedures for operating on these representations to extract numerical relationships between them. Presents a model for this mechanism and discusses its relation to later numerical knowledge. Contains 42 references. (MKR)

Presents activities to cultivate the tendency to see special qualities in numbers that can be played on certain calendar days. Includes games on the constant of the day, Fibonacci and golden ratio dates, primes, powers, December 25, and the day of the year. (ASK)