A cheap simple ammeter for batteries-and-bulbs activities

The use of batteries and bulbs to teach the fundamentals of circuit analysis has been with us for many years. Even recent innovations in pedagogy seem to rely on batteries and bulbs. In addition, the California Science Content Standards for fourth grade require that “students know how to design and build simple series and parallel circuits using components such as wires, batteries, and bulbs.” These standards go on to indicate that students should be able to use a compass to detect magnetic fields and know that electric currents produce magnetic fields.