The present study pursued the effect of Rational Emotive Education on irrational beliefs, assertiveness, and/or locus of control in fifth grade students. A random sample of two hundred students were pre- and post-tested in accordance with the Solomon Four Group Design. The Children's Survey of Rational Concepts From C, Revised Rathus Assertiveness Schedule, and the Intellectual Achievement Questionnaire were selected as instruments to measure irrational beliefs, assertiveness, and locus of control respectively. A ten week guidance program was presented to the Experimental Groups by twelve elementary school counselors using lessons from Rational Emotive Education: A Manual for Elementary Teachers. Pre-test and post-test scores were subjected to statistical analyses using ANCOVA and ANOVA. The results of both the ANCOVA and ANOVA revealed that a significant difference at the .05 level was evident only on the Children’s Survey of Rational Concepts which tested the rational beliefs of the students. One week after post-testing, fifteen students and five teachers were randomly selected from the Experimental Groups to be interviewed using questions that focused on the three variables: irrational beliefs, assertiveness, and Iocus of control. Their anecdotal remarks were collected to provide additional information on subtle changes in students that may not have been evidenced by quantitative data. The following is a summary of the results concluded from the study: 1. There was a statistically significant difference between experimental and control groups in irrational beliefs after Rational Emotive Education as measured by the Children's Survey of Rational Concepts. Anecdotal remarks lent support to the statistical evidence. 2. There was no statistically significant difference between experimental and control groups in assertiveness as measured on the Revised Rathus Assertiveness Schedule after Rational Emotive Education. However, assertive behavioral changes were evidenced in anecdotal data as reported by teachers and students. 3. There was no statistically significant difference between experimental and control groups in locus of control as measured on the Intellectual Achievement Responsibility Questionnaire after Rational Emotive Education. However, students did demonstrate very subtle change in locus of control as evidenced in anecdotal data, with teachers more explicit in reporting internality changes in locus of control than students. There are implications from these findings in the area of elementary counselor education and elementary guidance program selections. Also, alternative measures of assessing assertiveness in young students might be attempted which are more qualitative than quantitative. Future studies may attempt to modify rational emotive education to include lessons and activities designed to increase knowledge of internality and externality which may influence locus of control in upper elementary school age students. / Ed. D.