One possibility--and perhaps the most likely here--is that the power is fed first to the switch box and from there to the light. Then something else unrelated to the light is fed downstream from the black and white combo in the light box.

If that's the case, the red would most likely be the switched hot and should connect to the black wire of the light. The white wire of the light should be connected (or pigtailed) to the two whites in the box and the two existing blacks should remain connected (but not to the light).

You can verify or refute my assumption by taking the cover off of the switch and looking to see if it connects to a red wire.

And while you're at it, check to make sure that it isn't a 3-way switch with three wires attached. There's no other switch controlling this light, right?

[Just wondering: Any chance the light location ever had a multi-function fixture such as a fan/light combo?]

Hi Tom,
We figured it out. Turns out my daughter fried the dimmer switch by connecting the ground up to the hot. This is why the switch would not shut it of, it must have been fried open.
Thanks for your help.
.... john

Well, at least she didn't fry herself...

Yes...... that is definately a plus.
..... john