Training increased conservation responding but not verbalization of conservation principles. Stimulus desirability did not affect presence of conservation even in laboring-class subjects. (MH)

Six short articles concerned with mathematics education are included. (FL)

A computer program that allows students to simulate an experiment in probability is given, with specific suggestions on how to use and study the program. (MNS)

The "positive-negative charge" model is described and demonstrated with all four operations on integers. Its major advantages are that it is both concrete and complete. (MNS)

This investigation concerns the repeated application of the rule "take the sum of the squares of the digits." (MP)

Reports three experiments which examined kindergarteners' ability to conserve number in response to three forms of questioning: nonverbal, standard, and control. There was no indication that a full mastery of conservation could be elicited earlier by the nonverbal procedure. (Author/JMB)