Without effective preparation for practical classes, students are at risk of ‚Äö"information overload" as they attempt to simultaneously come to terms with novel technical or manipulative tasks as well as learning new concepts. Design of learning activities must take account of students' preferred learning stylesPre-laboratory preparation is one effective way to reduce cognitive load and to increase meaningful learning during laboratory classes.We designed on-line multi-media pre-laboratory exercises (Pre-labs) to support dissection-based practicals in a first year biology unit.