Option 1: Computational Physics
The estimated time to complete each of these is about 2 hours.
Kinematics and Gravitation (pick one):
2 Body Gravitation (Python or Matlab)
Falling Sphere
Projectile Motion
V2 Rocket (Excel)
Oscillators (pick one):
Rigid Pendulum
Falling Through the Earth
Boat Anharmonic Oscillator
Option 2: Physics Teaching
This is more open-ended, but you should demonstrate that you put 2 hours of work in; I strongly suggest you run your idea by me. If one of these isnt big enough, you are free to combine several mini-projects.