Presents a classroom activity in which students build and learn to use their own abacuses. Describes the lesson that combines mathematics, art, and social studies. (KHR)

Examines methods and types of estimation. Characterizes fruitful in-class estimation tasks by exploring the validity and possible extensions of "marble jar" estimation. (KHR)

The article suggests that Belcastro rods, which retain the basic properties of Cuisenaire rods but allow instant identification by touch, may be useful in teaching mathematical concepts to blind children. Drawings illustrate use of the rods in teaching such concepts as addition and subtraction. (Author/DB)

The importance of establishing a problem-solving atmosphere is stressed. Children asking "why" are on their way to strengthening their number sense. Curiosity should be promoted, encouraging children to test their own hypotheses and pursue their own predictions. An example with an eight-year-old girl is given to illustrate these points.…

Students have the opportunity to verbalize relationships that demonstrate the acquisition of good number sense. They are to develop clues about the answer to a problem without computing or telling the answer, and to state or write several things they know about the answer to each problem. (MNS)

Developing numerical relationships with calculators is emphasized. Calculators furnish some needed support for students as they investigate the value of fractions as the numerators or denominators change. An example with Logo programing for computers is also included. (MNS)

Studies of young children's sequence of development from counting to the beginnings of formal arithmetic are reviewed. Four essential basic skills are identified: use of counting words, enumeration, the cardinality rule, and quantitative comparison. The contribution of counting to the development of arithmetical proficiency is stressed. (JDD)

Examples are given of how calculator-sized pocket computers, which can receive, store, and execute BASIC programs, can be used in mathematics classrooms. (MNS)

Describes a method of teaching the order of mathematical operations based upon the psychological theory of conceptual generalization. (MDH)

Investigation of the links between understanding of the numeration system and representations of the counting sequence 1-100 of (n=77) high-ability grades 5 and 6 children revealed three dimensions of external representation: pictorial, iconic, or notational characteristics. (44 references) (MKR)

Interviews with 107 children, ages 4-7, about uncounted quantities, counted quantities, and numerical equations showed that the ability to predict changes to counted quantities increased with age. Only 7-year olds were able to use covariance and compensation in the purely numerical context of derived equations. (Author/MKR)

Describes a classroom activity in which students explore a real-life application of algebra by sending secret messages to each other. (MKR)

This article offers teaching strategies for developing number sense for children who are blind and braille users. Suggestions focus on developing number meanings, exploring number relationships with manipulatives, understanding the relative magnitude of numbers, developing intuitions about the relative effect of operating on numbers, and…

Two experiments were designed to examine whether gist memories are constructive inferences from verbatim memories or whether they are stored in parallel with the encoding of verbatim information. Being able to remember verbatim numbers did not help preschoolers and second graders remember either the global gist or the pairwise gist of those…

Contains biographical facts, contributions, quotations, and anecdotes about mathematician Gottfried Wilhelm Leibniz. Presents an activity in which students discover patterns in the sums of the reciprocals of the triangular numbers. Contains reproducible student worksheet. (MKR)