Annual Passholder and DVC are the only publicly available discounts I know of..
Annual Passholder and DVC Member discounts: 10 percent off for certain dates ONLY.
Passholder/DVC price for September 15, 22 and October 2, 16, 17, 23 and 24: Age 10 and older, $35.10; Age 3-9 $27.64.