The study was motivated by the lack of a formal in-service program for Newfoundland teachers on the use of the hand-held calculator in mathematics. -- The purpose of the study was to evaluate the effectiveness of an in-service model developed by the investigator, on the use of the hand-held calculator for mathematics teachers in grades five through eight. -- The sample consisted of 30 mathematics teachers in grades five through eight employed by the Port aux Basques Integrated School Board. The model was evaluated in terms of its effectiveness in changing the teachers’ attitudes toward the use of calculators in mathematics instruction, and in increasing the teachers’ understanding of the basic arithmetic operations on a calculator. -- To test the program’s effectiveness two null hypotheses were set up: -- 1. There is no significant change in teachers’ attitudes toward calculators as a result of the in-service program. -- 2. There is no significant change in calculator knowledge as a result of the in-service program. -- A needs assessment enabled the investigator to design the objectives of the program which attempted to change teachers’ attitude, to improve their understanding of the calculator, and to demonstrate how the calculator might be effectively integrated into mathematics instruction. The materials for the program were selected from the North Carolina In-Service Program developed by Immerzeel and Ockenga (1978). -- The pre-test scores for attitude and calculator knowledge obtained through a needs assessment were compared with the post-test scores obtained at the conclusion of the program. The scores were compared and analyzed using a dependent t-test. A t-value of 6.53 for attitude, and t-value of 9.71 for calculator knowledge were both significant at the 0.05 level, and resulted in a rejection of both null hypotheses. -- In addition to a significant positive change in attitude and calculator knowledge, the in-service participants rated all in-service sessions very highly, indicating that they perceived the program to have been a success. -- The fifth chapter outlines several recommendations suggesting some minor modifications to the model, which is recommended for use with other mathematics teachers
