This study investigated the comprehension and effectiveness of teaching formal, probabilistic decision-making skills to middle school students. Two specific objectives were to determine (1) if middle school students can comprehend a probabilistic decision-making approach, and (2) if exposure to the modeling approaches improves middle school students' decision-making abilities? "DECIDE" learning unit is developed to provide the context. This learning unit integrates mathematics, science, and decision-making concepts. Differences in students' pre- and post-test performance on a general decision-making test were statistically significant, indicating students can learn formal decision making in middle school and improve their decision-making abilities. Both race and gender variables were shown to have no statistically significant effect on pre- and post-test scores. (Contains 6 tables and 1 figure.)