The purpose of this study was to determine the effects of low difficulty and high difficulty testing approaches on the informational achievement of two groups of college students enrolled in a power mechanics course. Fifty students were assigned to two groups by a modified random technique, and treatments were randomly assigned to these groups. Control variables were (1) scholastic aptitude, (2) informational achievement, (3) anxiety, (4) attitude toward the course, and (5) number of previous courses in the field. The dependent variables were informational achievement, test situational anxiety, and attitude toward the course, with informational achievement being measured by low-and high-difficulty researcher-made achievement tests. Major findings were: (1) a significant gain in achievement in both groups, (2) a significant increase in test situational anxiety with the low-difficulty test approach, (3) no change in attitude for either group, (4) high ability students achieved best in the low-difficulty approach, (5) no significant achievement differences with the high-difficulty approach, and (6) the attitude of the high ability sub-group in the high-difficulty approach was significantly lower than that of other sub-groups. The achievement tests and statistical data are included in the apprendix. (EM)