Use this starter circuit for your ENGR 40M lab 2b prelab. The two logic sources on the left represent the two output pins on your Arduino, which control your motor driver. The motor is the component in the middle; it spins clockwise or counter-clockwise depending on the voltage applied to it.
Your job is to connect the MOS transistors and power supply so that you can control the direction of the motor using the logic sources (i.e., Arduino outputs). If you have everything right, it should also be impossible to short-circuit the battery!
IMPORTANT NOTE: The logic sources themselves should not be supplying any current to the motor. In fact, they should not be supplying any current at all.