We did 25 nights on the west coast last summer with 3 teens, similar ages to yours. We wanted to go to the Grand Canyon but decided to save that for another trip and just focused going down the coast. Also didn’t want to have to do any one night stays and rush around too much.
I booked all hotels apart from one VRBO in Santa Barbara halfway through our trip where I washed and repacked everything.
Buy packing cubes from Amazon and each have a different colour. They make the packing/repacking SO much easier between hotels-just thrown the bags in and out the cases. I also two large travel laundry bags to collect washing in as we went (family of 5, there was a lot!).
San Francisco is a bit iffy. Lots of homelessness/drug users. Obviously stick to the safer parts. Still worth a visit. We loved hiring bikes and cycling the Golden Gate Bridge to Sausalito. We started here and hired a car at the end of our 3 nights as you don’t need it in the city.
Then drove to Yosemite. Absolutely stunning and favourite part of the trip for me. Saw a bear! Jaw dropping scenery.
Then headed back to the coast to Monterey but did a few hours on the Santa Cruz boardwalk on the way. Kids LOVED this (and it’s where they filmed some of The Lost Boys).
Monterey we went whale watching which is another must do.
Driving the pacific coast highway is another must do. Stunning scenery at every turn. Really famous drive.
Stayed in Cambria and Santa Barbara on the way to LA. LA fun (do a cheesy celeb home tour) and huge but lots of iffy areas again. Walk of fame is fun for a visit but like a much dodgier Oxford street. Tacky and touristy.
Kids loved Universal studios, warners brothers studios and we went over to the Disney for a few nights too.
Spent last 4 nights in San Diego which is a great city and nice end point! Kids also loved a baseball game here.
In every city the drug problems/homelessness are very apparent and it’s really sad. San Francisco and LA the worst for this. I wouldn’t go back to them but I am glad that I have visited them once (and would recommend still!). It was a dream holiday all in all!!