This study examines middle school students' learning and motivation as they engaged in a multimedia enriched problem-based learning (PBL) environment for middle school science. Using a mixed-method design with both quantitative and qualitative data, we investigated the effect of a multimedia environment on sixth graders' science learning, their levels of motivation, and the relationship between students' motivation and their science learning. The analysis of the results showed that: Students significantly increased their science knowledge from pretest to posttest after using the PBL program, they were motivated and enjoyed the experience, and a significant positive relationship was found between students' motivation scores and their post-science knowledge scores. Findings were discussed within the research framework. (Contains 3 tables and 1 figure.)