As a project maintainer I wouldn't want an intern being the most familiar person with our Py3 migration, I'd rather students stick with new features or optimization and coordinate the migration process as a group-wide effort.
Without help, it is going to take a long time to get many packages converted to 3.x. I think the students can be invaluable in this process. Ideally, they will tweak the 2.6 code until it converts cleanly using 2-to-3. That sort of work will be easy to maintain.
IMO, this is the most important thing that can be done for Python at the moment. I would much rather this sort of work than having a student build a new library module and then not be around to maintain it.