Github is a web-based hosting service for Git repositories that helps to organize code in version control. Additionally it offers a great discount for educational purposes (for students, teachers, researchers, etc.): the Micro plan (5 private repositories) free for 2 years.
Get the Discount
Open Github Education and use the provided form to request the discount. Explain who you are and what the educational purpose of your project is. You will receive your discount after 1-2 days.