What type of camera should i buy?

I'm an IB Film student in high school. We have to shoot some short films. I don't want to shoot my films by my iphone camera, i want something more professional but not like Canon EOS.
better than iphone 4S
not like Canon
affordable

You can get a camcorder for about $250. It would be the right tool for the job. Much more zoom, better audio, and autofocuses better.

RetiredPhil is right. Use a DSLR for photos, and use a camcorder for videos. You need to use the right tool for the job and a DSLR "CAN" do videos, but it's main purpose is still photography. You'll get far better results (video and audio quality) with a $250 camcorder than a $3,000 DSLR.

Get a digital camcorder.