Dance performance photography with Nikon D3100?

My art teacher has asked me to photograph my schools' hip hop dance performance. I tried to shoot the dress rehearsal but the pictures were blurry and/or too dark. The stage was dark and only lit by stage lights which ended up drowning out the faces of dancers with the light.
How can I prevent all these problems? What settings (ISO, shutter speed, aperture) should I use? I'm using an 18-55mm f/3.5-5.6G ED II (non-VR) lens - the kit lens.

Yes, this is difficult shooting. Go up as much as you dare with the iso, 2500, 3200 even. Open the aperture all the way and start playing with the shutter speed trying to find the balance between overexposed faces and blurry.