You can try Searching for "camera" or "webcam" in your search bar.
If You can find it like that, you can use Windows Movie Maker to take a picture with your web-cam. When you open it, notice it has a "Web-cam" Tab. Take a short Video, Move the Scrubber to the frame you want as your image. Then click the "snapshot" tab. there you go it will ask you to save your image on your computer. (http://youtu.be/fvqXzsDFoCQ)
short video showing you how.
Source: My camera app was blocked on my school laptop so I had to find ways around that.