AAA is $10 off each ticket right now, I think.
Usually in the spring (I think? maybe Feb before spring break) Burger King will offer buy an adult get a child free coupons. Wendy's has had this deal, too.
I think Ralphs (local Kroger owned supermarket) or Vons (Safeway owned supermarket =) offers discount tickets but I'm not quite sure. Mousesavers will have those deals for sure. Also the local Costco.
I just checked mousesavers for the current deals. We were thinking of going just with the AAA one. Looks like there is a deal right now from Dairy Queen for the buy an adult, get a child free. If we went, I'd send my husband to get that and then go in line behind him and get $10 off my ticket with AAA.