Founded in 1916, the Santa Barbara Museum of Natural History makes for a great excursion to Santa Barbara with the kids. There are eight exhibit halls with permanent exhibits featuring birds, mammals, insects, ocean life, a planetarium and more. Many of the exhibits are "hands on" with buttons and interactive features that kids particularly enjoy. There are an additional two halls for changing exhibits.
You and your kids can roam the nature paths and visit the well stocked gift shop, full of educational items. I can vouch for the fascination kids (and adults) have at this Museum. It is a very comfortable museum that in my experience is rarely is crowded. The "Museum Backyard" area and gardens has a picnic area, stream and other enjoyable features. The pond and stream often have tadpoles that captivate the kids.
The museum is open 7 days a week and is closed certain holidays. As of July 2019, admission is $15 for adults, $12 for 65+ seniors and teens (13-17) and $9 for children 2 to 12 years of age. Become a Museum member and you don't have to pay for admission. The Museum also offers birthday parties for members. Tax-deductible family memberships are currently $99/year.