It's not even quite mid-semester yet and I'm beginning to hear from frustrated students. They've emailed their instructors 3, *3*, times and haven't heard back. They've called and left messages and haven't received a return call. Days have gone by with no response - and of course now the assignment they have a problem with is due tomorrow.
I always assume some exaggeration in these claims, really I do, but honestly a week is a long time in the life of a student. Students are busy. They have jobs, they have spouses, they have children. They have things to do and commitments beyond school. They have specific times set aside to manage their homework and study and if they can't do it then they may not have another time to do it. And we, as faculty with equally busy lives, need to be respectful of that.
That means you need to respond asap. Even if the response is that you don't have an answer yet and that you will have to respond again later you still need to let them know that much right away. Your student needs to know you received the message and that you are looking into it. The sooner you can give them a response the easier it is for them to rearrange their complex lives to meet the classroom requirements. So don't delay. Call or email right now!
(Photo Credit: sirspacepilot on Flickr, http://www.flickr.com/photos/sirspacepilot/5144846100/)