If it's a notebook, how often is he actually going to tote it around and use it on the road?

Given how most students such as myself use their notebook computers, I'd go with something that is not too big and has lots of battery life. A Dell Inspiron 600m would meet those requirements and your price level. The Gateway M320 and M405 would also be worth looking at; the M405 is a bit chunkier but has similarly long battery life.

In general you want to find something with a Celeron-M or Pentium-M processor. Anything else is going to be pretty big and not so great on the battery.