The majority of students at the university here (and I think most universities) have switched to using laptops. Most do not lug them around all day, but want something that can be used away from their dorm/apartment when they need a quiet place (I think laptops have reduced the number of arguments between roommates ). Laptops are great for students, but I also think that the accidental damage warranties are probably a good idea, especially for a teenager (not all companies offer these, but we have used the ones on our Dells to deal with things like dropped laptops and even drinks spilled on laptops). You may wish to consider some strict rules about where/when a laptop can leave the house though. We see more problems with laptop theft than we do with students breaking them.

I know some people aren't happy with Dell, but I have had decent luck with them (keeping in mind that we buy hundreds of them a year at the university) and they have great online deals if you watch techbargains.com and gotapex.com. We got 30% off the laptop I'm typing on now. These deals are often better than the volume educational discounts we get at the university (which can be frustrating at times).