For such basic use a basic laptop will serve you well. No need at all for an expensive ultrabook, unless you find weight and battery life important factors.
Only condider a chromebook if you're sure you don't need any Windows or Mac software for school (depends on the content of the courses of course), because chromebooks only run a limited range of Google apps.
Hey so I'm looking to get a new laptop for school. It won't need much grunt as I'll only be using it for school work, and probably streaming shows/ movies, and I'm not sure if I should be getting a ultrabook/ notebook/ laptop or chromebook. Preferably I don't want to go over $700 (NZD)