To Do

  1. The CdS can be used to control the blink rate of an LED in the same
    way as the pot was used. Check it out!

  2. Try different CdS sensors and see what variation in maximum and
    minimum readings you get. Try using two CdS sensors in the same circuit
    (one on analog pin A0 and one on analog pin A1, and use the Serial Console
    to see how much their readings differ.