nothin' better than yosemite
Yosemite Creek Campground is a cute little campground on the north-ish end of the park. All the sites are rented out on a first come first serve basis, so it's really a matter of luck if you can find a spot. The campground is strictly for tent campers, no RV sites. The sites are pretty nice! The one I had was not the largest, but it was flat and secluded which I loved. They all seemed to have picnic tables and a bear box for your food.
I think the sites also close down during the fall and winter seasons, so be sure to check on that if you're planning a trip.
In terms of the park, you'll never run out of cool things to do. Yosemite is one of my favorite places to rock climb. The routes are interesting and you gotta love that California granite. If you can hike half dome, DO IT. Also check out Yosemite Falls and Mono Pass.
Everyone needs to visit yosemite at some point in their life. It's amazing!