The teaching of Chemical Oceanography in the Faculty of Marine and Environmental Sciences of the University of Cadiz (Spain) has been improved since 1994 by the employment of a device for the laboratory simulation of estuarine mixing processes and the characterisation of the chemical behaviour of many substances that pass through an estuary. The equipment comprising the simulator is controlled by a computer system running the program OLE (Oceanography and LEarning), which was developed originally as a research tool in Chemical Oceanography (under Windows[R] environment). Later, on the initiative of several teachers, the handling of the simulator was simplified to allow its use as a didactic resource for teaching the various processes that take place in littoral systems. Since its initial development, many different natural environmental conditions have been simulated, and the behaviour of many chemical pollutants has been studied. On the basis of this favourable experience, the simulator designed appears to be a versatile tool that can be usefully employed in both academic learning and research work.