Being a Seattelite...
Seattle, the city where when evening approaches....
Everyone fights 2 hrs of traffic to go home out of the city to get away from it. LOL
As for standard attractions...
The zoo and aquarium are pretty fun if you're interested in looking at things. I haven't been to them since I was a kid though. Like the science center, they feel to be geared more towards the younger people. Oh... the science center Laser shows can be fun! The night shows are pretty cool. I think I went to a 11pm showing of Laser Floyd. LOL
If you are going to pike place market, you can often find free parking under the bridges, but do lock the car up nice and tight. You can also find parking right along the market and that is free, but you'll have to fight the crowds to get a spot. They do throw fish once in a while, and that usually gets a small crowd. Most of the stuff in Pike Place market is arts and craft, but in spring I'd think there should be a good amount of flowers.
While there, take a look at the "Ye Ol Curiosity Shop" on peer 54 if I remember right, and if you get the chance, the underground tour is pretty interesting.
If you drive up to Mukilteo, just about 20 min north.... 2 hrs if you happen to hit rush hour, I think the Ivars on the seafront is better there than the one in Seattle service wise. And there is a beach front they redid not too long ago which is full of rocks you can look for things under if you hit it at low tide. On the way up to mukilteo from Seattle, if you decide to make the trip, there is an excellent bubble tea and cantonese style chinese resturant in Edmonds, Exit 179. Pochi's is the name of the bubble tea place, and T &T seafood restaurant is the name of the restaurant.
Anthony's in Seattle, a sea food place I hear is pretty good eating too but haven't been there myself. If you make it to the U district, you can wander around the UW campus and get lost. In the "quad" the cherry's are likly to be blossoming in spring break time. There is a little resturant behind the health sciences building called "Aqua Verde" which is pretty good, and if you make it to the "ave"... which I think is "University Way NE", there are lots of little good eating for cheap. Pho Than, is really good pho, and prices are very reasonable. University Teriyaki is also really good.
You could always make a trip up to the top of the space needle to just say you did it, but it's costly the last time I looked. To get a city view, you can also go up to the top of the "Smith" tower. If you like shopping, you can go wander around Macy's and West lake center if I remember right, but myself have only been there 3x because I'm not a city person. The Alderwood mall is actually a bit better and only like 20 min north. Free parking and actually nets more money than the Seattle stores often because of the location.
Driving will be a pain if you choose to drive. One way streets galore, hills so steep you need to rev to get up them, parking nightmare... if you can, park it and walk. The bus system is great. There is a free ride zone downtwon, so in those areas in off peak hours, you can hop on and ride for free. Else, it's a few bucks for adults and less if you're under 18. I had a student U pass, so I'm not sure exactly what the fare was. I want to say if it's just local seattle downtown and you don't have to switch to sound transit, Everett transit, community transit or so on, it might only be 75 cents a person. Plus, busses run from like 5 am till 2 am M-F. You can pick out city cars by the scraped up bumpers. Ok, driving is probably not that bad, just not for me and not for every day. Just time trips in cars outside the hours of 7-9am, 12-1pm and 4-6pm M-F, and if there is a game, extend that 4-6 to a 4-8pm.
If you want, you can also hop on a ferry (cheaper on foot) and take a ride back and fourth if you like and stand on the deck just to do it.
That's all I can think of now. Enjoy spring break!
Mine is the 3rd week of march!