We are a few students working on a school project that will become a startup in a year.
As we want the project to work and be sure that the startup will work when we finish, we all work very hard on documentation and code.
The problem is that one of us doesn't want to join the startup in a year and only stays as a member of the school project.
Even though it's for school, our organization is the same as a startup (hence a workplace, this is why I'm posting the question here), I lead the team, we have a CTO and developers, including this member.
But as he won't join the startup, he always asks for "the easiest tasks" and is pissed when someone tells him something about his work.
I'm not that concerned, I go by the classical policy of "as long as the job is done I'm fine", but other team members start to lose motivation and patience towards this guy.
I don't want him to start feeling left behind, yet the rest of the team reasonably thinks it's unfair that someone can put minimum efforts and get away with it.
How can I make the team more united?