Hi, Brandy! Thanks for bringing your question to the Disney Parks Moms Panel!
Your kids will be at such fun ages to take to the parks! There are oodles of attractions in both parks that do not have height restrictions which means that the whole family can ride together. In my opinion, every area of both parks has something for everyone, so no matter where you are, both kids will have plenty to experience. There are some specific areas that I might prioritize over others, however. Mickey's Toontown in Disneyland Park is great for kids of any age. Your younger son will have a blast playing in Goofy's Playhouse and Donald's Boat and your older son can take a ride on
Gadget's Go Coaster. If your 3-year-old is at least 35" tall, he can ride this attraction too! If your kids like to explore things at their own pace, try the
Pirate's Lair on Tom Sawyer Island. There are bridges, caves, an old fort, and much more to discover on this island which makes it perfect for two adventurous boys.
Over in Disney California Adventure Park, I think you might spend the majority of your time is Cars Land. The theming of this land is awe-inspiring and the attractions here are so much fun! Your 6-year-old will absolutely love Radiator Springs Racers (40" height requirement) while your younger son can take a spin on Luigi's Rollickin' Roadsters and Mater's Junkyard Jamboree (both have 32" height requirements). They can also meet some of their favorite friends from the Cars movies and chow down on some delicious treats at the
Cozy Cone Motel.
I just know you are going to have an amazing time at the Happiest Place on Earth!
-Linda