Having the word 'honey' in their URL isn't all that Pornstar Honeys and Honey School have in common. They are also pretty much the same site once you get into all the content available.

Looking at just the main picture sections provided on the main page the sites have different content. There are about 2,000 or so sets of PornstarHoney pictures, while HoneySchool has about 1,500 of its own (both sites are nonexclusive and there is some overlap). The fact is, however, that the 300 or so videos are all the same and all the photo content that wasn't in the main section can be found through other links provided by the sites. There is no need to join both, but if you want lots of, mostly good-quality, nonexclusive content then pick one and check it out.