Pre-laboratory work has been shown to be an effective investment at undergraduate level in chemistry at the University of Bristol. A Dynamic Laboratory Manual (DLM) has been developed to allow undergraduate students to rehearse practicals using virtual experiments, video clips and a range of assessment support. The DLM has been shown to be highly successful in its goals. In this paper we describe the development and implementation of a DLM appropriate to post-16 students at school or college which also has applications in teacher training courses. First results from evaluation are presented which show an improvement in practical skill and cognition.