a. Arduino Stack (Proto-shield on top)
b. Red and Black Alligator Clips with Jumper Ends
c. Yellow Jumper Wired. 10k ohm Resistor
d. 10k ohm Resistor
e. Photoresistor (light sensor)
Connect the alligator clips to each wire end protruding from the photoresistor. It does not matter which pins you choose. Take the red end and plug it into 5v (5 volts) and plug the black end into the bread board.
On the same column plug one end of the 10k ohm resistor into the breadboard and the other end into GND (ground) finally take the yellow jumper plugging one end into the same column on the bread board as the black alligator clip and the 10k ohm resistor and plug the other end into any Analog In pin except 0 or 1 those pins are used by the motor shield to measure current going to the motors.
Be sure to program your Arduino to do an analog read on the pin you have plugged the yellow wire into. Or if you are using the Artbotics library, setup the sensor object with said pin.