I also take it that you are camping. Are you staying in the valley or outside the valley? Things to see are
Glacier Point/Washburn Point - Views are spectacular. You will reach Washburn Point a couple of minutes before you reach Glacier Point - stop there for some great picture taking, and one of the only places to see Illouette Falls (also called Hidden Falls from the Mist Trail to Vernal Falls) make sure you go to the end that overlooks the valley. Glacier Point has magnificent views of the valley. Be sure to walk the little trail to the end so you can see Yosemite Falls and the valley below
The Valley - this is so beautiful, and you can easily walk to the base of Bridalveil and Yosemite Falls. You can also take a trail (can be steep at points) to the base of Vernal Falls (there is a bridge there), or you can hike to the top of Vernal, Nevada, or Yosemite Falls. There is also an interesting visitor center there, and I highly recommend visiting. They have a replica of a little native american (I think they are the Miwok tribe) village, plus you can see how the valley was created, etc.
Trip to Mariposa Grove (southern entrance) will also take you by Inspiration Point, which gives you one of the most famous views of the valley. The Mariposa Grove is a grove of giant sequoias. During the summer you can take a tram to see some of the more famous trees. You can take the tram round-trip, take it one way & hike/walk back (we usually do this), or just hike the trails. On the way back stop at Wawona to see the Pioneer Center. We sometimes picnic here. There is a stream from the Chilnuana Falls with some nice swimming holes in this area.
Tioga Road to Tuolomne Meadows. A trip to Tuolomne Meadows is also very nice. These meadows are about 9,000 ft up (3,000 meters or so), and there is a lake and a stream that goes through them. Again, just beautiful, with some spectacular scenery, and worth a trip up there. We like to picnic next to Tenaya Lake up there.
You can rent bikes at Curry Village and ride the bike trails, you can hike along the valley floor, or take the trails up the mountains.
Yosemite is my favorite place on Earth, so I go there whenever I can.