OP here. Just thought I'd share our actual itinerary last week, for anyone who's planning a trip to San Diego soon with young kids. We had about a 5-day stay at the Omni La Costa Resort in Carlsbad:

Tuesday-arrived at resort by 5pm, dinner in Encinitas with friends

Wednesday-Torrey Pines hike & picnic, hotel pools in afternoon, dinner in Carlsbad with friends

Thursday-Legoland, dinner in La Jolla

Friday-Birch Aquarium/tidal pools, pool in afternoon, dinner in Old Town San Diego with friends

Saturday-quick sightseeing in downtown La Jolla, Balboa Park Museum of Man monster exhibit followed by playground time, Mission Beach boardwalk/Belmont Park rides

The two things I'd do differently: We previously lived in San Diego, and didn't realize how far Carlsbad is and how bad traffic is on the 5 north, starting around Del Mar up to Carlsbad! We spent a ton of time in the car. The resort was lovely, but next time we visit, we'll probably stay somewhere more central in San Diego proper, or maybe La Jolla.

Also, we had a red-eye flight Sat. night--the 5yo was great on the flight to SD (watched Moana 2.5 times, lol), but she slept terribly on the way back, and as a result, so did I! She adjusted well to the time change in SD, but was really cranky and jetlagged this morning before school.

Hope this helps anyone else thinking of heading to San Diego with kids!

We go to San Diego to visit family and have really enjoyed the beaches in La Jolla and Encinitas (I know going to the beach is kind of a no-brainer, but our kids love the ocean and will be happy for hours there). They also enjoyed checked out the seals in La Jolla.

OP here. Will add Birch Aquarium, Cabrillo (we've done an easy hike there before; had forgotten about this), Old Town, Carlsbad flower fields, and a couple others to the potential list. Great suggestions, thanks all!

Depends on what your child is interested in - these are things we've done over the years with our kids when we go visit my parents in SD:

Balboa Park - Zoo (of course), Natural History museum, Model train museum, Reuben H Fleet science center,
Birch aquarium/La Jolla Shores beach/Scripps tidepools/La Jolla Cove (cave kayak tour is fun but your kid might be too young)
Cabrillo National Monument (can get a Jr Ranger badge there) & tidepools at Sunset Cliffs
USS Midway/Star of India/Embarcadero
Old Town - the rock shop, candy store & Whaley House (supposed to be haunted) - these are all things I did as a kid growing up in SD
Carlsbad flower fields (if something is going on there)
Botanic garden in Encinitas http://www.sdbgarden.org/

Book United.

Get bumped and beaten.

Go home.

Your list is good. We went with our DC when he was 7 and did Wild Animal Park. It was great, but there is a lot of walking there. We did see tons of baby animals (I think 7-10 baby/young elephants alone), which was great. Your DC will probably be tired after a day there.

You can also go to Birch Aquarium at Scripps in La Jolla. Near there is the Children's Pool (NOT FOR SWIMMING), which is a good place to view seals and some sea lions.

https://www.sandiego.gov/lifeguards/beaches/pool

Belmont Park is fun, but a lot of the rides you have to be "larger" for. Our 7-year-old couldn't ride the roller coaster. We still had a lot of fun on bumper cars (or something).

Coronado is beautiful and has a great wide beach. It will be too cold in the water, though.

If your DC likes naval ships, there is the USS Midway, too.

Enjoy!

We're headed to San Diego next week for spring break, and are looking for things to do with a 5yo (besides meeting up with friends and their kids and just hanging out). We actually used to live there, but left when kid was still an infant. So, could use some help with our itinerary next week. We'll be staying at a kid-friendly resort in North County, but also expect to spend some time in San Diego. Here are a few options I can think of:

-(partial) hike in Torrey Pines
-Wild Animal Park
-Lego Land
-hanging out/scooting around Balboa Park; maybe a picnic
-hanging out on Mission Beach boardwalk; maybe doing Belmont Park amusement park
-picnic at the Gliderport

Anything else I'm missing? We're gonna take a pass on SeaWorld, but anything else that would be fun with a kindergartner that I'm not thinking of?