As far as I know, most, if not all schools still require you to collect teeth - it's actually much easier than you'd expect. And yes, you want to try to get a variety of teeth - often, if you go to an oral surgeon, you'll get primarily molars, but you also want to try to get quality anterior teeth as well.
Also, it's important to collect as many teeth as possible, because in all likeliness, at least half of the teeth you get, you won't be able to use for a variety of reasons.