Github, popular host for git repositorys of free/open source software (FOSS) projects, offers plans for educational purposes. They already host repositories for free for FOSS projects. They also fully embrace the open source development model and frequently contribute code. This is an example of a non-code contribution.
Students are eligible for a micro plan. These usually cost between $7/month and $22/month.
Teachers and student organizations can open up a free organization account. These usually cost between $25/month and $200/month.
Administrators of educational institutes can contact github directly to see if they can get a discount on a particular plan.