https://www.smartdestinations.com/san-diego-attractions-and-tours/_ptd_Sdo-p1.html
If you build your own pass on there, you save 20% at each attraction. Sometimes, you can find a free child ticket when purchasing an adult ticket for Legoland, so that may be cheaper. The Zoo has a 2 day pass that you can also use at the Safari Park. That brings the cost down nicely.
The Go Card gives you 3 days at a many attractions, but the places you want to go are all day things. So, you could probably choose the 3 most expensive and if you happen to have any extra time on those days, you can do other stuff on the list. I think most of that stuff will close by the time you get out of the Zoo, Sea World, etc. Here's a copy/paste:
Go San Diego Card
With the Go San Diego Card, you'll get access to over 48 attractions. San Diego Zoo 1-Day Pass, San Diego Zoo Safari Park Africa Tram Safari Pass, SeaWorld San Diego, Legoland California, Knott’s Soak City, USS Midway Aircraft Carrier, Harbor Cruises/Whale Watch, Birch Aquarium, all Balboa Park museums, and over 40 other area attractions. Visit all attractions within 3 days of first use. Restrictions may apply.
Adult
(Ages 13 & older)
$199.00
Child
(Ages 3-12)
$179.00