The informal subtraction strategies that children develop are discussed in detail, with the role of the counting-down strategy described. Problems and remedies for difficulties caused by counting backward and the double count are also presented. (MNS)

A model of subtraction development and the computing difficulties and research issues suggested by the model are outlined. Demands of simultaneous processes, difficulties with informal subtraction, and the impact on the counting-up procedure are discussed. (MNS)

Analyzes error patterns of kindergartners' mental addition task. Eight weeks of computational practice affected the errors of unpracticed combinations on a retest. Seven of 10 children mastered previously unknown combinations involving zero by learning a relationship rather than the practice and memorization of individual facts. (Author/YP)

Many children with learning handicaps have difficulty learning to write numerals. The source of numeral-writing difficulties and some things which can be done to teach or remedy this skill are presented. (MNS)