Little Amerricka Amusement Park

In the big red building by the main entrance, down the hall that is left of the counter where food is served

There are two single stall bathrooms, one with a changing table and one without. Be sure to check their operating schedule before you go, as it's quite limited. http://www.littleamerricka.com/info/hours On the other hand, as long as you don't plan on riding any rides, you can literally just walk into the park. No lines, no admission cost. A ways to the right of the ticket booths, by the mini golf course, is a small staircase that you can use to easily avoid the long lines at the ticket booths and enter the park from the parking lot.