The author explored the potential to promote students' understanding of difficult science concepts through an examination of the interrelationships among the teachers' instructional approach, students' learning preference styles, and their levels of learning process. The concept "air pressure," which requires an understanding of invisible, abstract, and process attributes, is classified as a difficult science concept. The results indicate that students' posttest and retention test scores were significantly affected by their levels of learning process. In addition, results indicate that meaningful learners performed better on the posttest after receiving procedural learning instruction, whereas rote learners performed better after receiving internal learning instruction. Students who were meaningful learners with procedural learning preference styles performed better than did others on both the posttest and retention test, whereas rote learners with external learning preference performed better on both the posttest and retention test than did other learners. Although this study did not show that matching students' learning styles with instructional style would bring successful learning for all, it did show that students with procedural learning preference styles performed better on a posttest than did others after receiving procedural learning instruction.