This is a packet that tasks students with working through different series circuits. A variety of situations are given that require students to apply the concept of current being constant in a series circuit, to calculate the equivalent resistance, and to apply the equations V=IR and P=IV.
I use a table method where students find the voltage, current, resistance, and power at each resistor, as well as for the total/equivalent circuit. In using this method, students can see how everything "fits together" more easily. Also, it allows them the opportunity to more easily check their work, as they can calculate the final voltage and final power two different ways, and make sure the answer is the same either way. For example, they can see that total voltage is equal to the sum of the individual voltages across each resistor, as well as the product of the current through and the equivalent resistance of the circuit.