1. Sunscreen
We didn't go a day in Florida without extra sunscreen in my backpack. That Florida sun is hot and relentless. We reapplied every few hours and luckily came out of a five day trip unscathed. Nothing will ruin a trip faster than a nasty sunburn. Buy a 3 oz. plastic container and fill it with SPF for your day at Disney.
2. Sunglasses
This could largely depend on the person, but I can't do a full day outside without sunglasses. Squinting in the sun can often give you a headache or make you feel sleepy. Plus sunglasses make it really easy to low-key people watch (a favorite Disney World activity)!
3. Cell phone
This is probably obvious to all, but what I didn't realize is how useful the Disney apps can be! Both Disney World and Universal have apps that let you make plans for the day, check wait times for attractions, look at menus for restaurants, and a lot of other cool things. We did the "Let's go see how long the wait for this ride is" thing a few times before we realized we could just check the app instead of walking to the other side of the park! Your cell is also important for keeping in touch with your group, and taking photos if you're not bringing a camera!
4. Poncho
If you didn't already know, Florida weather is unpredictable. We woke up to a down pour on the day we were hitting Magic Kingdom. Luckily, we had our ponchos in our park bags and stayed relatively dry until the rain eased up. You could bring a raincoat, but ponchos are lighter and easier to pack in a small bag.
5. Hand sanitizer
I don't know if I would call this absolutely essential, but it was definitely nice to have. Your hands are touching a lot of gross things throughout the day, and on top of that you're probably eating a lot of finger foods. We had a lot of burgers, fries, pretzels, and the like and it was nice to be able to sanitize our hands quickly before eating.
