The Stones of the Elements

I tried this story once before, but it just didn't work out. Now I have more time and I'm going to try to get this story going again!

The basic idea is that there are six friends who just got out of school for the summer. They're transported to another world one afternoon and are given control over one of the six elemental powers: light, dark, earth, fire, water, and air. Its up to these six to save the world!