This study reports research findings on the use of animated cartoons in a multimedia application meant to evaluate their effectiveness in supporting teaching and learning in science. The researchers have developed a cartoon-style multimedia application whereas animated cartoons where designed from scratch using appropriate programs. The study was carried out in various elementary schools of Athens, Greece, and 179 pupils aged 10-11 years participated in it. The research results provide evidence that the use of animated cartoons significantly increases the young students' knowledge and understanding of specific science concepts, which are normally difficult to comprehend and often cause misconceptions to them. (Contains 5 figures.)