It gets really tricky, really quickly. That is why you should talk to a lawyer if you are serious about the question.
There are many important questions.
Are you or any of the students receiving payment from the school in any way? Are you employees in a student lab, or receiving a research stipend, or receiving any grants or funding of any kind? If so, any work you create may be covered under 'work for hire' laws, or may be bound by other contract terms that were accepted as part of getting the money.
What school resources did you use? What resources does the University supply? Is the work entirely your own, or are you building from a framework or from other materials provided by the school? What contributions does your instructor make? Those contributions may be enough to consider the school a collaborator on the assignment, or even to make your project a derivative work of the school's. The exact details can be very important.
Does the school have a policy on copyright and other intellectual property which you agreed to? It is increasingly common for universities to require a release of rights, or they might require that all works submitted as part of coursework and degree requirements be treated as joint works. Many schools, especially schools with research departments or graduate studies, have learned that licensing student's work can generate significant revenue. Most schools have had their lawyers update the school's policies to ensure that they can get money whenever a student's work has significant commercial potential.
If you were working on the project for your own purposes and not for a school project then it would be a simple collaboration; a collaboration agreement would be sufficient.
Because you are turning the project in for a school assignment, and because the project is being used in consideration toward your degree program, and because the school may have contributed resources to the project, the school might acquire some ownership of the result.
It is an area to tread lightly.