Be prepared for all types of weather. Knowing the weather is important to make any trip more comfortable, especially a camping trip when you are closer to the elements. It is also a good idea to know the surroundings and climate of the area that you are going to. For example, if you are camping in Walt Disney World it is important to know that Florida is very wet year round. The ground is usually moist, there are frequent mid-day rain showers, and the occasional thunder storm. These things will help you factor in not only clothing, but cleaning supplies, tarps, awnings, bug screens, etc.
Many campsites, especially those close to theme parks, will have shared bathrooms and showers for guests. Get a great travel bag just for bathroom supplies where you can quickly grab everything you need for the shower and freshening up. Have one bag for each family member to keep things even more organized and easy to find when you are limited for time in the bathroom while others are waiting.
Speaking of waiting, with shared facilities you may encounter some waiting unless you like to be a super early riser for the purpose of having the bathroom all to yourself. If you have a site that is farther away from main buildings or the entrance of the campground, it can take some extra time to get where you are going as well.
Some theme park owned campsites will have extra activities for you to enjoy ,so if you need some down time during the day or a day to just decompress from being in a busy park, try to find a camp site with activities available at the camp property. There are many great state parks close to theme parks that have hiking, fishing, camping, etc. You may want to research national parks with campgrounds in the area of the park you are visiting. They may even have cheaper camping fees.
Many campsites all over are now offering wifi, be it free or for an added fee, because we are in the age of the smartphone being an extension of our body. That being said, don’t expect your campground to have wifi available even if it is a theme park site. If you are planning on using internet on your trip, you may have to get a temporary hotspot or hang out at the local coffee house for a bit.
If you are staying in a theme park campground you will want to have some items on hand for added privacy. Theme park camping is a bit different from regular camping in that the unwritten rule of not walking through campsites is not highly observed. Some good items to help give you a space all your own are screened in gazebos/shelters.
It can be a trek or even short drive to the nearest snack machine or food. Make sure to have plenty of snacks handy especially if you have kids with you. Hungry kids are grumpy kids. An added bonus is you will save money by bringing your own. Make sure to store them tightly and put them in cabinets or closed bins where animals can’t smell or reach them.