The ability of 135 first, second, and third grade classes to solve open sentences involving sums between 10 and 18 was investigated. Performance appeared to be related to grade level, operation, the position of the placeholder, and the existence of a solution within the set of whole numbers. (Author/DT)

A talk given at an ALA preconference on "New Dimensions in Acquisitions (Atlantic City, July, 1969). A plea is made for the U.S. publishing industry to speed up the adoption of Standard Book Numbers (SBN) to be assigned to all books in print as well as all books published in the future. Standardized customer numbers are also advocated, and…

Reported is a study of the interaction between figural and semantic abilities (as defined in Guilford's Structure of the Intellect") and success in a programmed unit in modular arithmetic. The subjects were prospective elementary teachers. Significant interactions were found between both figural and semantic factors and methods of instruction.…

Methods are presented for teaching the meaning of exponential functions, Euler's formula, De Moivre's theorem and Maclaurin's series for exponentials, cosine, and sine to juniors or seniors in high school. (JG)

Reported is a study which compared two instructional methods involving discovery learning and a verbal didactic instructional method. The verbal didactic method was significantly better for immediate learning; the verbal didactic method and a guided discovery method were better for retention. No differences were noted regarding transfer. (CT)

Investigated was the feasibility of inducing number conservation through training kindergarten children on reversibility tasks not related to the criterion measure. (JG)