A study examined the effectiveness of a spatial learning strategy, the Graphic Post Organizer, implemented for an extended period of time. Subjects, approximately 150 eleventh-grade students enrolled in a "regular level" American History course at a combined upper-middle, middle, and working class suburb of Chicago, Illinois, were separated into control (50 students in 2 classes) and experimental (100 students in 4 classes) groups. Subjects in the experimental group received instruction in the use of the Graphic Post Organizer and used the strategy for an 8-week period, while the subjects in the control group received instruction in the SQ3R strategy (Survey, Question, Read, Recite, and Review). Pretests and posttests tested student comprehension and recognition of relationships between concepts in unfamiliar passages adapted from their history textbook. Results indicated that: (1) 80% of the students appeared to have mastered strategy usage at an 80% level at the end of the 2-day training period; (2) many students did not transfer strategy implementation from guided practice to independent practice; and (3) while subjects in the control group achieved a higher mean score on the pretest than did the treatment group, the treatment group achieved a higher adjusted mean score on the posttest than did the control group. Findings suggest that spatial strategies assist students in increasing their text comprehension and that modeling of the strategy is an appropriate method for the teaching of spatial strategies. (Two tables of data, 2 figures representing Graphic Post Organizers, a list of Graphic Post Organizer terms for the branches of American government, and 13 references are attached.) (RS)