To use the Theme Park you need at least 5 distinct food sources in quantities of 1000 or more. For each type of food that you spend in this manner the Theme Park gets a base happiness per hour of 25. At 10 foods the happiness per hour exceeds that of Luxury housing. At 20 or more foods the amount of happiness produced is astounding.
Each time you spend 5000+ food to operate the Theme Park it will operate for an hour. While it is in operation you can spend another 5000+ food to extend its operation time for an additional hour. And you can continue this for as many times as you have food available to do it. This works a lot like stoking a wood burning fireplace to keep the heat coming to warm your house. However, with this particular fireplace you must spend as much food each time as you did the previous times. So if you spent 10 foods when you started it's operation, each subsequent extension of the operation must have at least 10 foods to spend as well. If you can spend even more on subsequent concurrent operations, then it will increase the happiness for the entire duration remaining. Through careful management it's possible to get a lot more out of the Theme Park than you put into it.
While not in operation, the Theme Park uses very little resources, just enough to maintain itself. However, while it is operating, it uses considerably more resources. This may cause you to go to negative production while it is operating. You can experiment with this by simply operating it for an hour at a time to see if you can afford it.
Keywords: Happiness Buildings