If your future physicists know how to construct simple circuits, include resistors, and use a multi-meter to measure voltage, then you might employ this lesson on Ohm's law. Each lab group investigates the relationships among voltage, resistance, and current. They vary the voltage and record the current. They graph their results to discover any correlations. The student lab sheet is written in an open-ended inquiry fashion, not providing exact details of how to proceed. It can be used after introducing Ohm's law.