TWO GROUPS OF WHITE SIXTH-GRADE CHILDREN, MATCHED FOR INTELLIGENCE AND DIVIDED INTO AN UPPER-MIDDLE-CLASS GROUP (GROUP A) AND AN UPPER-LOWER-CLASS GROUP (GROUP B), WERE EXAMINED AFTER THEY HAD HAD A 6-WEEK SOCIAL STUDIES UNIT ON MEXICO TO DETERMINE THE RELATIONSHIP BETWEEN SOCIOECONOMIC STATUS, ACHIEVEMENT, AND DIRECTION OF ATTITUDE CHANGE. BOTH GROUPS HAD BEEN PRETESTED ON STANDARD TESTS AND ON THE MEXICAN ATTITUDE INVENTORY PRIOR TO THE INSTRUCTION IN THE UNIT. DIFFERENCES IN INTELLIGENCE BETWEEN THE GROUPS WERE CONTROLLED BY THE USE OF COVARIANCE IN THE ANALYSIS OF ACHIEVEMENT TEST SCORES. TO CONTROL VARIATIONS IN THE INSTRUCTION, THE EXPERIMENTER TAUGHT BOTH GROUPS. GROUP A SCORED SIGNIFICANTLY HIGHER THAN GROUP B ON THE ACHIEVEMENT TEST ADMINISTERED AFTER THE UNIT'S COMPLETION. ALTHOUGH THE ATTITUDE INVENTORY WAS NOT VALIDATED, GROUP B WAS FOUND TO HAVE MOVED SIGNIFICANTLY TOWARD REJECTION, WHILE GROUP A MOVED TOWARD ACCEPTANCE, ALTHOUGH THE TREND FOR THIS GROUP WAS NOT STATISTICALY SIGNIFICANT. THE FINDINGS OF THE STUDY MAY REFLECT THE MANY VARIABLES THAT COULD NOT BE CONTROLLED AND WEAKNESSES IN THE TESTS AND INVENTORIES USED. THIS ARTICLE WAS PUBLISHED IN "THE ELEMENTARY SCHOOL JOURNAL," MARCH 1959. (JL)