Welcome to the Disney Parks Moms Panel, Yesenia. I'm so glad to hear you'll be heading to the Happiest Place on Earth for the first time with your 9 year old.
My son is 9 years old too, and needs to snack often. Sometimes he even gets hungry an hour after mealtime. When we head to Disneyland Park or California Adventure, we always pack some snacks in my daypack so my kids can have something light, especially while waiting in line for Character Meet-and-Greets or rides. While Guests aren't allowed to bring coolers larger than 6-pack sized (please see this
list of prohibited items), you can take with you small amount of snacks and drinks in your bag. Just be sure they're not in glass containers.
You'll find that there are lots of dining options throughout both parks. Although we bring a few snack items with us, we often end up indulging in the treats found throughout both parks. Our family favorites include Mickey-shaped soft pretzels (who doesn't love their foods Mickey-shaped!?), cheddar garlic bagel twists and boysen apple freeze from Maurice's Treats in Fantasy Faire, as well as Dole Whip sold at the Tiki Juice Bar outside the Enchanted Tiki Room in Adventureland. And for some magical reasons in California Adventure, the corn dogs at Corn Dog Castle and soft serves at the Paradise Pier Ice Cream Company taste so much better than what we have back home!
I hope this information is helpful for you, Yesenia. Please visit us on the Panel again if you have further questions regarding your upcoming trip.
Sending you Pixie Dusts,
Kiki