sometimes the six flags website has some decent deals. Also, maybe try Kroger and Groupon.com. I've seen deals for six flags there occasionally. Good luck
If you buy them online they are $34.99 compared to $50-something at the park. Other than that it's hard to find anything. I was just there earlier this month.
This. I buy mine online all the time and get it at that price. Better deal than the coke cans I think. If for some reason you can't find the online deal. Here is the printable coupon http://www.arlington.org/couponsandspecials/coupon-detail?id=30
it's funny how no one outside of Texas knows that Six Flags is a Lone Star reference and the birthplace of said theme park...
http://www.swosu.edu/administration/hr/docs/sixflags.pdf that pdf has a link that lets you buy tickets online for 28 bucks not sure if that is the cheapest or not