Hi there, Alexandra! Welcome to the Disney Parks Moms Panel and thanks for your question!
You can absolutely bring water bottles, snacks, and other kid essentials in to the Disneyland Resort. In fact, I never go to the parks without at least one water bottle, lots of snacks for my little one, and an extra change of clothes, just in case. Just make sure none of your items are packaged in glass containers and you'll be all set. I'm not sure about the ages of your children, but if you have a baby, you should know there is a
Baby Care Center located in each park. These are relaxing, cool places to change your baby, feed him/her, or rock your baby to sleep. They also sell over-the-counter medication and other baby essentials.
Also, if you are bringing a stroller, it can act as a place to store all your items. You can also
rent a stroller at the parks if that is more convenient for you. I recommend tying a balloon or other identifying item to your stroller so you can easily locate your stroller when you park it at designated stroller parking locations throughout the parks.
Finally, one last tip if your kids might be interested in splashing around
Princess Dot Puddle Park in "a bug's land" in Disney California Adventure Park. Pack water shoes for your little ones in your backpack or stroller. Shoes are needed to play in this splash pad, but you won't want their regular shoes getting soaked. Bringing along a towel or two might be a good idea as well!
I hope you and your family have a wonderful time at the Happiest Place on Earth!
-Linda M.