I am a 15 year old high school student who is a programming enthusiast. I have started a software & tech "company." I say this in quotes because we have not incorporated legally, we do not pay our workers, and we do not make money as of right now. We are the classic basement startup, with bi-monthly meetings literally "in my mother's basement."

Currently, we are developing a videogame. I am the main programmer of the game, but under my command I have many other high school students. Some of these do music, some of them do art, some of them do writing. (Our game is very story-centered)

I have a serious problem. My art team, currently consisting of three high schoolers, is very inefficient. (They procrastinate everything) Art team has been rocky from the start, with people leaving and others joining over time. As it stands, I have 3 artists in my art team. 

My question is this: Without adding new artists, how do I motivate my artists (and my crewmen in general) to do stuff? I can't pay them, as we make no money and I would quickly run out of money. **I guess this is more of a "club" than a "company," though we treat it somewhat like a company.** I don't want to threaten to fire them as my only motivation. I want to somehow reward them for their achievements and promote EFFICIENCY. I really want to show them how much I appreciate their work, without making it weird or "cringy." What are some motivating factors?

Any help would be awesome!
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