Series/Parallel Circuits consists of a power supply, two volt meters, one large ampere meter and four smaller ampere meters which are connected to individual light bulbs. The four light bulbs and their accompanying ampere meters are on rotating blocks which make it possible to connect them to prominent bus bars in either serial or parallel fashion. Regardless of whether or not the light bulbs are connected in series or parallel, 18 watts are consumed to power the lamps. The various meters make very clear what the voltage and amperage measurements are in any of the configuration which the visitor can try.