Using the Cobbler kit to break out your pins, take one of the IO to control a relay. You want to use an external power source to driver the motor. Read up on relays if you're not familiar, but it should be your best bet.
simulate this circuit – Schematic created using CircuitLab
Credit to Scott for mentioning the Pi can't drive the current necessary to turn on the relay. Therefore, I added an npn transistor. Also diode was added for pin safety. From my understanding, the Pi has an accessible 5V from the Cobbler kit? I suggest using this for the collector of the transistor.
I left V1 arbitrary, perform tests to see what voltage needs to turn the motor. That, or find the Datasheet. V1 is where the DC motor will attach to.
Finally, the motor looks like a normal DC motor.