Knott's Berry Farm in Buena Park California was America's first theme park. Started as a family farm in 1920 by Walter and Cordelia Knott, the farm first attracted visitors to it's Chicken Dinner Restaurant in the 1930s and 40s when as many as 4,000 chicken dinners were served on Sundays. To give waiting customers something to do, Walter developed the Ghost Town, which became the first of the park's themed areas. Today, Knott's Berry Farm is the 12th most-visited amusement park in the country.
Check local grocery store ads for the discount tickets and discount yearly passes. These discounts can be found on the last page of the full color circulars and on the store web sites.
Check the Knotts Berry Farm web site to see what discounts they are offering. The best offers can be found at the beginning and end of the season, but they offer some discounts throughout the season.
Consider checking out locally available soda cans. Pepsi and Coca-Cola often offer discounts that apply when you bring a specially marked can to the park.