What would be a simple aerodynamics simulation software for a student?
If you have only two weeks it may be best not to go running into a maze, but you may wish to have simple and complex approaches running side by side.

As others have said, it would be helpful to know the parameters of your assignment.  Are they interested in the theory, or do they want to see something flying?

The most important thing will be the airfoil shape as far as lift and drag, but glider airfoils are easily obtained on the Net (airfoil tools). Next would be wing loading, which can be obtained from existing models and data from birds.  Design can be your choice, but starting from scratch, a standard sailplane planform will serve well.

Remember to have your CG near your Clift, slightly forward, and your elevator trim slightly up. For an indoor free flight glider a high aspect wing with some dihedral and an upright vertical stabilizer will help make it fly straight.

Although the theory behind gliders is well known, getting one to fly right will be a learning curve from scratch. Leave at least 2 days for test flights, and plan on extra Styrofoam and glue for repairs. Good luck!